Xi seems willing to prop up Russia indefinitely

Definitely not.

Remember: China wants it’s former territories back that Russia took over during what China calls “The Century of Humiliation”.

Xi wants Russia’s war with Ukraine to continue for as long as possible, because the longer the war goes on for, the weaker Russia becomes, and the easier it will be for China to take back that territory.

Money is fictional anyways. If they want to, Moscow can print literally arbitrary amounts of Rubels. There’s no way they’re gonna bankrupt.

Germany printed more money during a certain world war…

It didn’t work out great for them

Yes but sanctions take years to take effect because they accumulate over time.

They’ve been slow rolled which has slowed the effects, but Ukraine’s “kinetic” sanctions have accelerated the effects back up.