This war has shown that tanks are not an end-all be-all weapon, in that there are *lots* of superior anti-tank weapons out there. So the new tank doctrine will evolve to be to use them strategically, and with a lot of finesse.
And of course, to hit the enemy where they don’t have anti-tank weapons in abundance, and to get your tanks out of there when such weapons show up in force. Which severely limits their operational time in an area.
In WWII, the Russians lost a LOT of tanks because they used them separately from infantry. Tanks without infantry support are very vulnerable, even then. But then, after getting their tanks punished for a while, they would pull them back and send in human waves of infantry without tanks to face German machine gun nests. This did not work.
So far in Ukraine, the Russians have lost the majority of their heavy armor already. It waits to be seen if the Ukrainians are any smarter with their use of tanks.
I attended the Armor School at Ft Knox in 1973.. “Doctrine” then was, “on the battlefield, consider yourself a 55 ton infantryman.”. That is even more so today.