You cannot divorce one from the other.
[edit] (They earned units that they could exchange immediately or at some future time. Whether or not that amounted to wealth is based on what those units could or did turn into at the point of measure within the framework of the society in which they exist.)
But yes, they were kept inside the country, which is a separate issue.
Yes, that’s exactly why people who actually lived there now regret its collapse. The younger the person, the more they were oppressed by the KGB.
Taxes are a great way for citizens to give back to the pool used on them, proportionally, and for governments to insentivise and discourage behaviour ( e.g. lower taxes on electric vehicles and raise them on more polluting types). Saying taxation is theft is a great way to out oneself as incredibly naïve and with approximately zero understanding of how anything related to government, politics or economy functions.
> You earned your wealth. It's not the government's
A common misconception among libertarians and alike; that's outright false. Pretty much everyone in a regular developed/ing country, especially in a centrally planned economy like the USSR, has wealth because a society and a government enable it. Be it with infrastructure, education, regulations, monetary system, or whatever. For examples how important those are for any wealth generation, look at Venezuela or Turkey.