So now that Ukraine destroyed more than 4000 out of those 3000, there are no tanks on Russian side of battlefield?
In your haste to make shit up you may have overdone it a little bit. Ukraine claims to have destroyed or captured ~2500 (Oryx confirmed ~1400).
Russia has been
taking tanks from Lukashenko and also bringing
rusty "unpickled" T62s to the war zone - I doubt they'd do that if they didn't have severe shortages.