Well, western countries are in need of rubles right now this can be the game changer because the Russia's announcement that unfriendly countries can only buy their oil with ruble means USD actually becomes worthless in Russia,this ain't affected the USD value but it just showed that USD may fall and lose its reserve currency status if they lose more countries relationships and start imposing sanctions.
No, the situation does not look like this. It is not entirely clear to me why or why you are presenting information either "twisted" or taken out of context. Let me explain - no matter how Russia boasts of its exaggerated greatness, the sanctions themselves hurt the financial sector. Yes, a significant part of the assets, including banking ones, were blocked, and here, indeed, Russia no longer manages them. And yes, disconnecting from SWIFT introduced a lot of restrictions. BUT. It is for oil / gas / coal settlements that accounts are not blocked and hotel banks were not even introduced under sanctions just so as not to violate these mutual settlements.
Regarding rubles and normal currencies: Russia still has gold and foreign exchange reserves, which are under the control of Russia. But as you understand, this is the money that Putin and his accomplices want to keep for themselves. Who needs rubles - no one! And dollars, euros and gold are a chance for a carefree old age
Therefore, the game of the "world ruler" began, who, as he says so, everyone will start doing it - we transfer all payments for gas and oil only in rubles, otherwise we will turn off everyone. But of course, everyone relied on these tricks of the crazy "great ruler". Therefore, Russia tried to make such a move - here they say you have rubles for our debts. But ... that's the difference - the West is used to working within the framework of agreements and laws, Russia - to take such illegal steps. And the contracts clearly spell out how payments on these debts should be made, and the form of calculation and terms and conditions. Conditions not met (form of payment) - I'm sorry, you're a dummy and a loser....