I think they are all immature and stupid.
Saluting is not immature.
Neither are knuckle crunching, blow kiss and bro love. That doesn't mean you don't look ridiculous when using them. The salute is perhaps the most mature of them all, but you can't deny how stupid it looks as a winning taunt (in FR it looks decent, as does bro love). Still, saluting and bro love are 18 y/o skater kid mature and the rest is 10 y/o ADHD kid mature.
We want actual mature ones. Until then I'll either do nothing or smoke.