Creative Speculation

The military may revolt, but it will revolt against the generals and not putin. Just a guess, but 30 years is a long time, and any old guard are likely gone.

All that will be left in the upper echelons will be loyalists and toadies. Think of what would happen if tfg were in place for 3 decades. There wouldn't be a guardrail or anything approaching disapproval from that crowd. They are in on the take. They are in on the delusions. They will blame anyone but themselves or dear leader.

They won't turn on putin.

The army will walk home before the generals acknowledge there is a problem.