France also had a massive colonial empire to fall back on for manpower and 10% of the French population didn't leave the country. Ukraine is also more than likely taking that much or slightly below that much causalities as they were on the offencive against an enemy with the firepower advantage.

Russia has also taken 100k causalities, not a 100k dead. It's probably like 25k dead and 75k wounded. America and its allies suffered 340k dead and another 1.34 million causalities.