Considering what percentage of men are capable of weighing 125lbs(very, very small). Then, of that very small percentage, how many go into MMA? It's not his fault but he's fighting in the most shallow division in MMA, both in numbers and in skill. As long as he reigns there it will take a "fluke" to beat him. He's already cleared out the division and it will only take 2-3 wins for a new prospect to get a shot. Then they aren't developed enough to face someone like him.
Yes, he's that baddest 125lb fighter in MMA but it stops right there until he DTBG. He may not even be top 5 in one weight class above. Then to 145, he may not be top 10. By the time you get to LW, he's getting beaten badly by 90% of the division. No chance against a WW and above.
The "baddest man on the planet", or for that matter the top 100+ BMOP you've never even heard their name. As far as combat BMOP it has to be a HW. Guys who fight people their own size or bigger and sometimes giving up 20,30 + lbs in weight. In the HW division there is nowhere to run from fighting men your own size. No cutting 30-40lbs to fight smaller men.