One thing tho, that letter he posted doesnt seem to be from when he was employed by WWE but rather after he had left and was still using social media accounts with names and handles with a trademark that WWE own, which is different to WWE requesting social media passwords of its employees. The two are not the same thing. If i was WWE or any other pro wrestling company i would send Ryback the same letter, whats the point of owning a trademark and gimmick if i allow people to continue to utilise it after they leave, im not protecting my trademark and as a result every other trademark i own is in danger as other wrestlers will start using gimmicks online and in rival promotions and cite the ryback case as a defence.
In Law you can also lose rights to a trademark if it is proven you never made sufficient effort to protect it.