They aren't.
https://www.ringsidenews.com/2020/07...-wwe-pays-for/
They pay for any injuries you suffer in the ring...but that's it. After your career is over and you are left a shambling wreck of a human being...they cut you loose.“So our talent are all independent contractors, so we actually don’t provide medical insurance for our talent,” McMahon stated. “We pay for all injuries, any surgeries or anything related to all in-ring injuries. We do have substance and abuses protocols that we offer our talent both current and retired. So anyone that’s ever had issues with drug and alcohol abuse, they can be a part of this program. WWE itself, for our employees, we do have health, medical and overall wellness and mental health.”