This is my original quote. Notice how I specifically say injuries, not death. You can make it through a career as a soldier or plenty of dangerous contracting professions without ever suffering a TBI. A career in mma guarantees you several, and most fighters will suffer quality of life impacts post-retirement. There's no reason to underplay the extent of brain trauma in the sport, it's part and parcel with it.
You still don't get how unusual Bellator and the UFC's contracts are. If an oil rig worker signed a contract for a 5 year gig, but decided half way they wanted to be a mechanic, they would be perfectly able to. If a fighter decides they are done with mma halfway through a 5 year contract and decides they want to be an Olympic juduka, the UFC or Bellator can bar them from doing so. That's incredibly unusual in this day and age.