He specifically meant T-62M variant which has more advance optics and ATGM capability contrary to T-72M
Russian Armed Forces want to modernise old T62s and turn them into 800(!)
T-62M. How realistic is this?
The T62 entered service in 1983(!!!).
That is, almost 40 years ago.
I.e. all suo and missiles are made according to the technology of that time.
And I am sure that there are no production lines left in Russia to make both.
One retired Russian military officer told me that during his service (late 80s in the training unit, tanks of the TOF coastal forces) there wasn't a single tank in his unit equipped for t62m, and there were not even instructors for training.
No, of course, I'm sure there were instructors for t62m somewhere, but their number is vanishingly small.
At the time they believed T62 was already a history, and the future was T-80, T-90 and upgrades of T-72.
Bottom line: no instructors.
Sheksna outdated and do not know how to use them.
The number of produced Sheksnas is unknown, it is impossible to revive the production process in a short time.