That was a very small ruling class exploiting pretty much the entire population. That's very low levels of inequality.

Typically that would be viewed as high inequality. If the ruling class of .1% controls 99.9% of the wealth then the "average wealth" and the "median wealth" will be extremely different aka wealth inequality.

That would be high inequality, yes.

However, if the ruling class of 0.1% has 10% of the overall wealth, then that would be very low inequality. I would expect that to have been closer to the truth under the old USSR or the old Cuba, see the graph at: https://voxeu.org/sites/default/files/image/FromMay2014/novo... taken from: https://voxeu.org/article/inequality-and-property-russia-190...

That's high inequality, isn't it?

Also I always laugh at how the CPSU was supposed to bring true communism but instead just kept the power indefinitely.

"After all, why not? Why shouldn't I keep it?" heh

It is possible to have very high inequality and [pick one] comfortable/uncomfortable poor people.

How much someone has relative to their neighbour doesn't control their quality of life.

Yes, exactly. What matters is do you have the resources to comfortably meet your needs or not. It does not matter if some people have many times more resources than you, that does not affect your situation. You might be envious, but that's neither here nor there really in your day to day quality of life.