I think any Russian exporter collecting foreign currency for sale of goods has to hand over that currency in exchange for 80% of the value in roubles, something like that.
The worrying aspect now is what looks to be an attempt to cut of Russia from the rest of the world. I suppose some wont see that as worrying Perhaps it isn't but all sorts of things have been known to start wars. This time it would be the big boys against each other as it has been a few times in the past. Times change and the bangs get bigger and bigger. The low yield neutron bomb is banned - in conventional sense only 1 to 1.5 mTonne according to the limited info available. Dam things may well be adjustable.