It remains too soon to comment in detail on the current upheaval in Kazakhstan as it is simply impossible to figure out what is happening, with multiple conflicting accounts and claims coming from many sources. Rather I want to comment on a deeper question that has been brought up in connection with this, although not central to it, but one that affects Kazakhstan's Central Asian neighbors as well: what alphabet should they use? This is something that is an ongoing issue in several of these nations with changes happening.
Prior to 1928 all of what are now the five Central Asian nations that used to be republics of the USSR: Uzbekistan, Kazakhstan, Turkmenistan, Kyrgyzstan, and Tajikistan used some variation of the Arabid alphabet, with Russia conquering the Samarkand and Bukhara khanates only in the late 1800s. This reflected the dominance of Sunni Islam in all these territories culturally and politically. This area was not even part of the USSR when it was first declared on Dec. 30, 1922, having a vague status while nominally under Bolshevik control, but ransacked starting in the 1920s and through most of the 1930s by traditionalist rebels known as Basmachi, a word that actually means "bandits."
Only in 1928 with Stalin's coming to supreme power in the USSR did the efforts to "modernize" and integrate into the USSR more formally begin in Central Asia. Part of this effort involved eliminating the use of the Arabic alphabet, with initially the Latin alphabet being introduced. This reflected the local ongoing modernization movement associated with pan-Turkism (a part of a broader movement known as pan-Turanism), which sought to unify all the Turkic speaking people under a single political entity, with the push to adopt the Latin alphabet coming out of Turkey, where Kemal Ataturk had replaced the Arabic alphabet with the Latin one as part of a Europeanizing secular modernism. That this movement had spread to Turkic speaking parts of Central Asia made it easier to push it through to adoption (note that in Tajikistan they speak an Iranian-related language, not a Turkic one).
Given this connection with the pan-Turkic movement it is not surprising that eventually Stalin became frustrated with this and wanted a greater national unity within the USSR. So in 1940 he imposed the Cyrillic alphabet used in Russia on all the Central Asian republics. At both times there was resistance to the alphabet change, with this even erupting into violence at certain points. Curiously the first place I read about this was in Thomas Pynchon's novel, Gravity's Rainbow, where there is much discussion of aspects of ethnicities and their issues and movement during WW II.
One might have thought that given how long it had been in place there would be no further changes. But with the fall of the USSR at the end of 1991 and the Central Asian republics becoming independent nations, the issue reappeared, with indeed each alphabet having its own symbolic as well as practical implications. Clearly maintaining Cyrillic implied remaining reasonably closely tied to Russia in various ways, economically and politically. Rising Islamic fundamentalist movements urged a return to Arabic, although that has not happened in any of these five nations, with only Tajikistan having such a movement being sufficiently strong that there has been any serious push for that to happen. The main rival has been the Latin alphabet, offering both a return to links with Turkey, but also with the West, especially the US, but also to some extent an opening to China, where there is much more knowledge and use of the Latin alphabet than the Cyrillic.
Two of these five nations have retained Cyrillic with only minor pushes to change, the two smallest: Kyrgyzstan and Tajikistan, which despite much economic influence now coming from China remain strongly linked to Russia and part of its Collective Security Treaty Organization (CSTO), which has sent in troops to Kazakhstan, also a member (the other members are Russia, Belarus, and Armenia). I do note that while it remains a part of the CSTO, Kyrgyzstan is the only one of these five to have actually had more or less democratic governments for periods of time since 1991.
Curiously the one that first changed to Latin and has stuck with it almost immediately with independence was Turkmenistan. This is the most isolated of these states, indeed of the former Soviet republics. It is a strict dictatorship run as a personality cult and has stayed out of all alliances, although it does belong to the UN. It is the third largest in size in both population and land area. It manages to maintain its isolated independence due to having major natural gas supplies by the Caspian Sea, exports of which have kept Turkmenistan from needing economic assistance from any outsiders.
The largest in population and second in land area is Uzbekistan, which was long ruled by its former Soviet Communist Party Chief, Islam Karimov, who died in 2016 to be replaced by Shakvat Mirziyoyev. The Karimov regime was probably second only to Belarus in maintaining something close to the old Soviet economic system, with Karimov as a full dictator. Since his death his successor has introduced various market reforms, but not much in the way of political liberalization. But Karimov made a move with independence to adopt the Latin alphabet. But this has not been completed and both Latin and Cyrillic are used, although there has been a long run trend to full adoption of the Latin alphabet. it is ironic that while Karimov followed the Soviet economic model, he sought to remain more independent of Russia than say Belarus. But the alphabet issue remains live and not fully resolved.
Which brings us to the now troubled Kazakhstan. I note that almost nobody was predicting any kind of political upheaval there. It was one of the few former republics that moved up in its ranking among them on real per capita income, with Kazakhstan long a major exporter of oil and natural gas. Like Uzbekistan it was ruled by its last Soviet Communist Party Chief, Nursultan Nazarbaev, now aged 81. There was lots of corruption and political repression, but that is true in the other Central Asian nations, and Kazakhstan seemed to be doing better than them, with Nazarbaev making deals with both the US and China, while maintaining a primary and close relationship with Russia, not only by being in the CSTO but hosting Russia's space base at Baikonur and with Russian troops helping to protect its oil wells in its southwestern areas near the Caspian Sea (second in population in the region, it is the largest in land area and the second largest of the former Soviet republics, with its eastern boundary on the Xinjiang province of China, and it having a Uighur minority population). Kazakhstan has long had a diverse population, with about a quarte being Slavic, mostly Russian, with many of those moving into northern Kazakhstan in the early 1960s as part of Khrushchev's Virgin Lands program. But up until now conflicts between the many groups there have not been a problem.
Regarding the alphabet issue, it long continued to use the Cyrillic alphabet. But then in 2017, the current president, Kossym-Jormat Tokayev, who attended a KGB higher academy in the Soviet era and has served as ambassador to both China and the UN, convinced Nazarbaev to make the switch to the Latin alphabet from the Cyrillic one. At the time Russian President Putin expressed unhappiness about this move, which may have had more to do with China than the US, with a major railroad part of China's Belt and Road Initiative goes through Kazakhstan. Nazarbaev hand selected Tokayev to succeed him as president in 2019, with Nazarbaev moving "upstairs" to be Chair of the National Security Council. In the face of the current upheavals, Tokayev has removed Nazarbaev from his position.
In any case, the Russian propaganda outlet RT has claimed that Putin has demanded as a condition to send troops in Tokayev should recognize the Russian annexation of Crimea and also readopt the Cyrillic alphabet. It seems that Putin has not insisted on this and has sent troops in even without this change. But this is a sign that this remains an important issue for Putin, and we may yet see pressure on Kazakhstan to revert alphabetically.