It all depends. Yes, I agree that in almost all cases it should be about the music. However, it is the entertainment industry. Unless you're out of sight, part of entertainment is presentation. The people you entertain have a ton of bearing on what's "acceptable". Granted, I say this as a stage actor. Visuals affect people in odd ways. It'd surely be shocking to go to have surgery and the doctor has a barbed wire choker tattooed on. Just like it's odd to see a clean cut guy in a suit in a metal band...when he's not doing it ironically. Are either technically wrong? no. But it's just the way their "customers" perceive them. My tattoo is so I can be onstage in underwear and all is hidden, I made that choice knowing my profession but wanted a tattoo. Playing in a metal band, it's always been the go all out mentality. Imagine even watching Swan lake and a ballerina has a sleeve tattoo, that'd shock me haha. But when it comes to an Orchestra, that's a different story. Again, most people probably won't see you And most I've been in or seen, they all wear tuxes or long sleeved apparel anyway, so that should be fine.
I remember singing in an Opera once where the Baritone soloist came to rehearsal dressed like a lumberjack, but come showtime, you'd never know. I think eventually it won't matter. But in the classical music scenario of things, the hoity-toity uppity crowds usually want that classic look...I say usually because I have seen a couple guest soloists that were not that at all. Very expressive in their appearance with colorful personalities, and they could really play.
All in all just because something is the norm, doesn't mean it's the rule. BUT, it's the norm for a reason.
I remember singing in an Opera once where the Baritone soloist came to rehearsal dressed like a lumberjack, but come showtime, you'd never know. I think eventually it won't matter. But in the classical music scenario of things, the hoity-toity uppity crowds usually want that classic look...I say usually because I have seen a couple guest soloists that were not that at all. Very expressive in their appearance with colorful personalities, and they could really play.
All in all just because something is the norm, doesn't mean it's the rule. BUT, it's the norm for a reason.