As if those countries had anything reasonable.

Why don't you look to Europe instead?

Russia is literally capitalist though????

This is true. Russia is in fact a good case study of late-stage capitalism. You see, in American capitalism, everyone started equally and then had to build up to their monopoly positions today. In Russia, some people just started out with monopoly positions, due to corruption. So if we want to see what happens due to monopoly positions, we can just look there.

Americans all started equally? You sure, that the early comers, to america, who got huge amounts of land and resources started equally to irish and itallian immigrants?

And even the modern monopolies... Gates and his mom getting him a deal with IBM is a bit different than someone else without a well connected mom.

And looking at tax rates companies like facebook pay, I think corruption is very well alive in USA too.

Started equally, quickly became unequal, but nowhere near as quickly as Russia, which started at maximum inequality.

There is a middle ground.

“As a policy regime, it is described by academics as advocating economic and social interventions to promote social justice within the framework of a liberal-democratic polity and a capitalist-oriented mixed economy.”

Some of the world’s most successful countries are run that way.

It is called social democracy.

I'd like to think there are a wider group of options than a binary choice between "American Late-Stage Capitalism" and "Venezuela"

I'm sorry to have to break it to you but Venezuela and Iran are capitalist countries.