Both UFC and WWE athletes are already independent contractors and have to privately buy stuff like health insurance while participating in a literal combat sport (UFC) and wrestling over 200 days a year (WWE). It's already a race to the bottom.

The UFC and WWE have already vertically integrated their respective niches. They're pretty much the only game in town. If no one cared when WWE bought ECW and WCW--and no one cared when the UCF bought Strikeforce--nothing is gonna be done now.