Havent watched mma in a while, but last I checked MMA had the best bjj guys/wrestlers because thats their only outlet. Demian maia, vinny magaielies, and dean lister etc
they have to learn multiple arts (boxing included)
Damian Maia is as great BJJ, but he is not the best in world, there's guys who can school him in BJJ in dojos and also people who are champions in that sport.
That's the point I'm making
Floyd Mayweather is without a doubt the most skilled boxer on the planet
Like you say they train boxing, but that doesn't make them good at it.
They are only a hand full of complete fighters in MMA, you can count them on one hand, and that's why boxing is better right now.
It's more beautiful to watch. A lot of MMA looks sloppy, and this is coming from a fan of the sport.
Bret Rogers went from working at Sam's club with no experience, coming into MMA for few bouts ten to fighting Fedor in a competitive fight he almost won.
Bret Rogers could not have hope into a boxing ring and fight Vitali, he'd get killed.