Russia picked the exact worst time in history to revert. This is a time when all technology, medical knowledge, materials science, propulsion, weapons, etc. are improving exponentially. By cutting themselves out of the science communities and the information sharing, let alone the manufacturing capabilities, Russia, who was already a techno-laggard, will be left in the dust while near-alien level civilization surrounds them. Their only hope to avoid this fate is to quickly rejoin the human community and help repair Ukraine to the extent they can. This would require drastic changes in leadership which seems unlikely. They will find even their most advanced weapons will be essentially neutralized by geometrically superior tech so at some point, they could also be crushed militarily with no actual recourse or deterrent threat.