Russia would not be able to take all of that territory with 80,000 troops.
But they could get their Mariupol to Kherson land bridge as well as control of the North Crimean Canal.
It’s now 100K+.
And remember, this is not Operation Desert Storm, with the USA needing months to send troops to Saudi.
This is on Russia’s border. Plenty of Russians right behind the 100K.
“Russia would not be able to take all of that territory with 80,000 troops.”
If they had a referendum in that part of Ukraine, I wonder what percentage would vote to be part of Russia? I believe, some sections are primarily Russian. It is easier to take over and hold territory if the population is behind you. That works both ways.