The further away a fighter is from HW, the less I care. I want to see the best fighters in the world and they fight at HW.
When I look at the UFC HW champion, I know that there are likely fewer than a handful of people in the entire world who could beat him. I find that amazingly impressive.
When I look at the UFC Bantam weight champion, I wonder how many millions of people could beat him in a fight. It isn't nearly as impressive. That's not too say they can't put on a good show, especially against someone of similar skill level and weight, but I don't find it nearly as intriguing as watching 2 of the world's absolute best fighters compete against each other.
More "belts" = more "champions", which equate to more headliners to fill shit level fight night cards and watered down PPV's.
For example, I look at WMMA like I look at Pee-wee football. There can be competitive matches but there's no way I'm spending top dollar to watch it.