Have a look at the 'demographic pyramid' of the RF population
https://www.populationpyramid.net/russian-federation/2020/
To be fair, it's based on reporting out of the RF from 2020 so it does not represent the waves of mostly-male out-migration that happened since then - nor does it show the casualties from their invasion of Ukraine. And we all know the RF never lies, right?
OK, see that bulge starting at 30-34? These are the people leaving the RF / dying in 'meat wave' assaults. Now look at the younger generations. Notice there are a lot fewer people in those brackets? At a minimum, this means that the RF population will be a lot smaller. The 2030s were always going to be the last decade they had the under-50 male population to attack a neighboring country, *particularly* using their WWI tactics (trenches, meat waves) - and I *think* the Ukraine war has brought that endpoint forward maybe 5 years.
OTOH, WTF do I know?