Russia walked this backed:
https://www.reuters.com/business/energy/russia-will-not-demand-immediate-switch-gas-payments-roubles-kremlin-2022-03-30/Their messaging is confusing and their economy is too fragile to further restrict themselves from global commerce, so you can expect something like this to not go through. It sounded like an empty threat from the start and a mere desperate attempt to avoid sanctions. Appears Russia still has India and China open to them for unrestricted trading, but they cannot reasonable expect to cut off trading from the rest of Europe and keep their economy afloat.
Yeah, I don't expect them to just shut it off. This is more posturing but they might eventually go on with it in the future. After all this means they'd be getting Euros in exchange.
The action of shutting off would really be not immediate as there are some existing contracts that need to be filled.
Maybe, after those contracts expired, European countries will assess the situation and push thru the shutting down of Russian services.
But if they can't find immediate alternatives or replacement, they may possibly continue to pay Russia, but now in rubles.
They will definitely weight the situation, but they won't be shutting down Russian gas if they can't find alternatives.