>>>Yes, it is. The Oplot is a modernized T-80 which has been around for almost 40 years now so it’s “mature” and not terribly difficult or risky to build.<<<
More like a T-64 and a crappy unreliable diesel instead of gas-turbine.
Good condition T-64s would still be devastating platforms for engaging Styker-type and BTR-type vehicles. While the poor armor is very vulnerable to even lighter shoulder-fired weapons the T-64’s main gun with modern ammo is a threat even to today’s tanks.
At Fort Benning we wargame against OPFORs with obsolete CCCP vehicles and especially in an urban environment Blue losses can go quite high against those systems.
Perhaps Thailand would prefer diesel engines as there are some advantages.