Demonetisation isn't biggest issue as it's very unlikely that they make much money from ads. Finding alternative platform where to upload videos isn't impossible too. But actually, you can't replace Youtube as you don't get such reach anywhere. 500k subscribers, hundreds of thousands views on every video - you simply won't make such things on alternative platforms.
While Ruzzian channels are already "monetised" by their "patrons", that is my guess anyway, the rest of the world is not sitting idle anyway. At least the EU is now patrolling actively looking for attempts to influence the European elections and the local elections. There is a whole list of sites that are deemed to be organised to create a certain opinion of Ruzzia being directly closed.
https://www.politico.eu/newsletter/eu-election-playbook/how-russia-is-targeting-the-european-election/
But those are just sites, the larger platforms such as TwitterX or Youtube have their own policies and should be treated as potential sources of disinformation by default when using them.