As long as his wife/SO likes it, you should too.
If you or your friends want to set an example, shave your head and go full Barkley/Jordan (pick your fave) before you see him next.
BTW, I never went the combover or hairpiece route. My hair had been thinning since my early 20's, after basically a full 'fro just a few years earlier. After a few decades of the top thinning and cutting it closer and closer, I slicked if off 7 years ago. The Norelco triple header is my morning friend
Now unrecognizable to HS classmates, but memorable to people I interact with regularly, like retail clerks and teachers/staff at the kid's school.
It's a bold look, not for everyone. Helps immensely to not GAF about such things, which was the case after my wife died and I quit working.