"It’s gonna be most painful for the oligarchs and people in their environment who are used to consuming massive amounts of foreign goods."
If 'tax the rich' works and reduces the power of the rich, then hasn't the West just taxed the rich of Russia and reduced their power to remove Putin?
Democrats can't have it both ways. They propose a billionaire tax in the USA to reduce the power of the rich to interfere with people in charge, then actually implement a billionaire tax in Russia and expect it to increase their ability to interfere with people in charge. It's an illogical position to hold.
"Btw even the USSR which was generally much more autarkic couldn’t survive without foreign currency for energy exports. What makes you think modern Russia could?"
If there are sanctions in place, what are they going to spend the 'foreign currency' on?
You can't eat dollars.
"so assuming there are countries willing to accept them they might be more likely to choose that"
The 'leave for other countries' is a globalist position. Most ordinary people are rooted in social support constructs on the ground. They don't leave, and prefer their own country.
In fact the attitude to those who leave from those who remain is likely to be good riddance to bad rubbish.