The "facts" show that most pros use a 2 handed BH (most men, almost all the women).
Navratilova said it is a safer bet. And she is one of the most well-known one handers, and no, she is not obsolete because she played Chrissie all her life who had a 2 hander and she knows what it can do.
Isner said he prefers it for stability on return of serve.
These are the facts.