People want the world to be simple and make sense. The cold war was great for this, as it presented two simplistic idealistic world views in competition.

Some people saw through capitalism and understood that freedom in the west is not all that it's made up to be. Not wrong. But then they make the fallacy of concluding that the alternative they are presented with is good, which would be Soviet communism.

Of course many people understood that both alternatives are oppressive, but once you discover some "forbidden knowledge" it's easy to start going a bit insane and to disregard evidence that goes against your world view, because clearly there is a great conspiracy at work. If you make the mistake of arguing with radicalized people they always have some stupid anecdote that they believe serves as solid evidence of any crackpot theory they have. In this sense it's just like conspiracy theories, and it tends to be the same type of people: lonely men who feel the world has treated them unfairly.

Authoritarian-leaning people need to believe that there is a good authority out there who wants them well and that they can follow. For the authoritarians that lost faith in the west, Stalin provided a strong alternative and remains iconic among these bootlickers. Putin just doesn't offer an alternative in the same way.