historical accuracy
Seems some things were even worse than shown:
https://www.telegraph.co.uk/films/0/truth-death-stalin-really-happened-night-forever-changed-soviet/
Also there are some critiques of its accuracy, but they don't seem that bad.
https://www.calvertjournal.com/opinion/show/9122/the-death-of-stalin-review-iannucci-buscemi-russell-beale
at the time of Stalin’s death, Molotov had long been sacked and Zhukov demoted to the provinces; Beria’s eventual downfall, which the film squeezes into a few days, actually took several months and was prompted in part by events in East Germany