Eastern Europe is simply poorer than Western Europe. Their style of government doesn't have much to do with it. There's less wealth to hand around. Whether inequality is higher there or not I can't say.
I compare those to Scandinavia and there is not question that inequality is higher Eastern Europe. And that is part of culture, not via political system or how poor those are. As no matter what the political system will be called, the system will always be mold to correspondence to local people and their cultures by those local humans. That is why corruption is bigger problem in some areas vs some another areas.
There is certainly a difference between European ethnic groups that manifests in behavioural and cultural differences. Slavs seem the least suited to 'democracy'.
We're seeing how hollow these 'protections' in the West really are. Looks at how many of these constitutional protections, rights and checks were breached against Trump, for example. How Snowden or Assange were treated. How the Capital Hill January 6th people have been treated in the US - some of them are still in solitary confinement for minor chargers like 'trespassing'.
The West was under autocracy for 2500 years and we built the best (and fairest) society ever. Yet we've had democracy for the last century and we've been declining ever since.
A few months ago Lukashenko was confirmed to be the Grand son of Stalin.
His policies worked whereas Ukraine is a cesspole of jewish Oligarchs who want to restore the old jewish possessions at the Black sea.
Jews destroyed the Russian Empire. Putin rebuilt id, basically from scrap.
I think both of them did an admirable job.