While a mild pain, I don’t see Russia really having that many issues if they can’t just wire money from A to B.
Russia sells oil to India, India puts rupees or some other representation of currency into an Indian bank account and then Russia buys some finished Indian goods from that bank account.
This isn’t far from regular banking where everyone just tries to keep flows balanced. All that’s new is being unable to directly “balance” payments if they go out of whack too much.
Do they lose a few percent doing this? Probably, but the spike in oil prices makes up for it.
If you just hack you don't need any of that though. Balancing, goods delivery, currency controls... Drain a western company, mix crypto for optics, give it to Iran or DPRK or whatever in exchange for munition
Plus India and relatively reasonable countries are not especially keen on trading with Russia, while they are friends they also want to be friends with West. Remember India has big problems with China and who's gonna help them against China? not Russia
People are willing to override a lot of their ethical concerns (and accept potential long term pain in favour of short term gain) when it comes to slightly cheaper oil, gas, labour or any other need and want.
A few countries got themselves in a pickle after shutting down local coal production in favour of cheap and cleaner Russian gas…