The question is what would they gain in reworking DRK to be specifically more interesting? It's blatantly obvious they have no desire to interact with the tank playerbase on a whole.

What they did in 5.0 was purely intentional, and so was the similiarity between Inner Release and Delirium. Much to its dismay, they are very clear in their approach albeit in a very non-direct way. What they are trying to do is lowering the skill ceiling to make tanks accessible to everyone. You could argue DRK is an alternative to your 3 other tanks in regards to more interesting gameplay, but that isn't true anymore and most likely will stay that way.

I think what people truly dislike is the fact you took a job with its own identity and completly stripped it naked in a completly unreasonable fashion. Why the developers are doing this is beyond me, but it probably goes to show that they don't care about our opinions as much as we would like to admit.

With all of that said, your HW DRK is a relic of the past. A time where developers generally could be more experimental, because the prospect of losing millions of players wasn't there at the time. They won't miss out on the sweet bucks guys, can't blame em' either.