With people inside them, they are basically coffins waiting to be destroyed by drones or guided missiles.
Hire some kids in Nevada to control them remotely and they could be a more effective weapon and since there would be no need to make them habitable, cost savings could be made and their range could be vastly improved.
Ukraine is the 21st Century equivalent of the Spanish Civil War - testing ground for the next war’s weapons, if not tactics.
No way I'd want unmanned tanks if I'm on the battlefield as an infantryman. Tanks and infantry must be integrated to be effective, and that requires face to face meeting between combat commanders. The idea that your tank platoon or company commander isn't on the battlefield would alarm me as a maneuver element commander.
There also is the element of physical care - daily maintenance, fixing thrown treads, getting bogged down, etc. etc.. Tanks need crews to keep them running and operating, not just to drive, load, and shoot.
Unmanned tanks would just be a bad idea. A long way off until that is remotely (pun intended) practical.