The greatest threat to Russia over time was the economic advances being made in eastern Europe while Russia continued to decline becoming increasingly dependent on its natural resources for economic viability and that wealth going largely to Putin and his "friends".
As this prosperity creeps closer to Russia, the Russian people can see the price they are paying for have a greedy dictator and Putin needed a distraction and to demonstrate his power.
I give Putin less than a 50% chance of surviving the Ukrainian war. The "distraction" has shown the underlying weakness of Russia. Its military is not as formidable as believed and its declining population no longer allows it to project the power it did when it was the largest nation by far in Europe.
The Russian "empire" is over and if Russia is to survive, it must be part of a global alliance. NATO is the obvious choice based on religous, racial, cultural, and geographic affinities.
NATO is not Russia's enemy. it may end up being Russia's salvation. Like Germany, France, the UK, Italy, Spain, Poland, and Austria, the time for being "the" super power of Europe" has come and gone. Today's world requires far more people and economic power than Russia will ever be able to assemble. Instead, Russia could become a critical partner in the NATO alliance, but most likely that won't occur until someone else is in charge in Russia.