It's still a good thing.
I would rather it only be 1 match instead of 2 and the match go back to WM instead of being it's own PPV, though
It being its own PPV is fine. It allows the MITB matches to get more time and focus, and thus play themselves out better than they would on a WrestleMania card.
I agree with making it one match rather than two, but I'm on the fence about it. It forces them to, quote-unquote, "make new stars," but WWE tends to book MITB winners like shyt after they get the case and hold it for a while, thus making them look kind of second-rate when they DO win the belt. Of course, Miz would be the fukking exception to this since 2008.
I'd rather have the KOTR back with a SummerSlam title shot hanging in the balance, but I'd be fine with a better booked MITB. The fact that New Japan did the best iteration of the MITB gimmick is kind of pathetic, to be honest.