As exciting as T-14 looks on paper and the few parades a T-14 prototype appeared in, prudence prevailed. The T-14 is a new design which has not been in action and current estimates put the cost per tank at $4 million. Upgrading a T-80U to something similar (in performance) to the T-90 costs less than a million dollars per tank. In the end it’s what you can afford, and rely on, that gets built. While the T-80 entered service in the late 1970s it turned out to be an effective vehicle to upgrade. No one is building anything like the T-14 so for the money an upgraded T-80 is competitive.
When the T-14 was unveiled with Russian glee and something akin to panic in the West, I doubted that the Russians could afford it.
And I noted reports that the T-80 would be upgraded (buried in that Weekend Data Dump, I'm afraid).
Still, it is interesting that talk of the extinction of heavy tanks has once again disappeared as major powers look for new heavy tanks.