What’s the point of premium tier 9s?

I understand that it’s another tank to use and that’s all good, but the main appeal of a premium is usually the ability to make credits. And tier 9 premiums don’t make the best credits at all because of the high shell and repair costs. The only real upside I could see is the ability to train crew. But for example the new m103m that’s coming out for BP is a really bad version of the tech tree tank. I’m not one of those saying that all premiums should be better than their nations tech tree but atleast lower the repair cost a bit. Would like to hear opinions!