Its not like You can send it to enemy's base and win. Its mobile battle station, very hard to kill when supported. And Itp definetly worth price. Saved my ass many times when Jp4s and stuka could not handle.
And it does not need to fight against stun shot like IS which is op in current form.
Is2 for me is nowhere as scary as kt.
Then thats a psychological problem then. The KT is big and intimidating but what it can actually accomplish is eh, not much unless it's a very specific circumstance. It's no mobile battle station anymore than the other heavy generalists are. A SU-76 can pen it just as well as a StuG III a IS2.
The KT isn't bad, it's just very situational and inefficient. I think it should get better vet and with reduced vet requirements and that would go a long way towards making it less efficient.