If you just need a bullet proof gun to support infantry, that might work, but it won't have good infrared sights to see very well compared to modern tanks. It would just fire where it was directed. Do you think that would be useful?
Well, given how quickly Ukrainian troops have been killing the more modern tanks, I think the T-54s will be VERY useful.
As Commie Cookers.
You really think that the Russians have even moderately trained crews that will be able to effectively work those T-54s?
Based on what's been seen in the later stages of 2022, the answer to that is a resounding no.
The T-54s, and their crews, are going to die ever faster and in ever increasing numbers.
The way it's going we're going to be seeing T-26 and BT-20 tanks being pulled out of museums and sent to the front any day now.