Technically the ussr collapsed because externally it had to settle accounts in the US dollar and low oil prices - it’s only export - couldn’t provide sufficient hard currency to do this but your point is still correct. Reagan knew this and leveraged it to the maximum even to the point of ruining our own oil economy and increasing our reliance on and strengthening our “allies” in the Middle East some of whom we later had to topple and some of whom we still struggle with today. It’s notable that this lesson wasn’t lost on China who long resolved that it would never run out of hard currency the way the USSR did. Russia on the other hand... as you point out they can’t seem to realize a diversified economy is one that collaborates and is open.
It's even worse than that. The ruling elite knows that on the one hand it's non-removable, but on the other its days are numbered (Putin is quite old and he won't live forever; what happens after he dies is anybody's guess), so they pillage and burn whatever they can while they can, with impunity. Diversifying the economy would require a long term view. The folks currently in power don't even realize anything is wrong per se - oil and gas money works pretty well for them.
