I hate the predictability of sound when a band walks on the stage, and you correctly nail the style of music based on "outfits". I see all these kids now a days "dressed for success". Whatever happened to musicians wearing a t shirt 4 days in a row on tour till they get to the next stop and hopefully get a free t shirt along the way? It was about the music.
I miss those days.
/rant
I don't think it's a bad thing(image and music). Like with goth music for example, the connection between outlandish and often dark clothing and the effects/atmosphere heavy music makes a lot of sense. The same could be said of a pscyhadelic band dressed like mad hippies. There is a kind of connection there that if people like one, they like the other. A bit like when you see a music video and think "Wow, that really went with the music". When you go to see a band live, it's an audio visual experience. If I'm going to a garage rock concert, I'll expect some dirty T-Shirts like you mention. If I'm going to see some ridiculous power metal act, I'll expect they look a bit silly too. There are too many guys that just stand there nowadays, t-shirt and jeans playing "indie rock". At least if you're going to look "Normal", do a funny dance or something like Ian Curtis.
If it goes with the music, then it's okay. You're presenting a false dichotomy about image and music when many of the founding fathers of modern rock were very elaborate dressers. "We look one way, but we play a totally different kind of music!" can become as annoying and gimmicky as the most annoying and gimmicky glam rock acts.
The thing is you're making the mistake of associating "dressing well" according to "nice" standards with "dressing well" in more creative, outlandish standards. People do this a lot, they mix up vanity with self expression and I hate it because it leads people to presume anyone who looks different cares only about their looks, and what do you know, everyone starts dressing in jeans and a t-shirt convinced it's "true" individuality. That's shit, if you're being goaded into dressing like everyone else you're not being more of an individual for disregarding one possible way in which you can express yourself. You don't waste metal effort "thinking" about how to dress since that's not how the brain works and we know that. And it doesn't cost any more if you raid second hand/thrift shops(can be less then).
Again, "image" doesn't have to be shallow. Vanity, mainstream fashion is shallow. Dressing creatively or interestingly in some way or another is not any more shallow than a painting on the wall is shallow because it's 2 Dimensional and pure "Image". The art of mixing and matching clothes with your personal appearance is creative in the same way a guy who designs characters for a role playing game, comic book or fantasy movie is. At the end of the day though, it's more difficult for social conservatives to live in a world where people appear different from each other on the surface, so they use the concept of "maturity" and other such memes to drive people away from it.
People have been codded into the contrary position because it's easy to associate image obsession and subculture with 14 year olds, and nobody wants to be a teenager. It's just a shitty form of McCarthyism. But either way, it's nonsense and I'm tired of people saying that dressing funny doesn't make you an individual, yet then turn around and say that they're somehow more "genuine" for wearing boring ass t-shirts and jeans. Dressing a certain way does not make you an individual, on either side. But it is a GOOD THING regardless, pretty things are nice, diverse things are nice. People have forgotten that. And hell, it's still one way in which you differ from the guy next to you so it can still be part of who you are.
I hate how everyone dresses the same nowadays. I think it was kind of important went Rockstars used to dress up a bit because it set a good example. If even our rockstars can't look different, who can? Lady Gaga? Fuck that, since that IS one good example of someone who's pure image(and not a very good one at that). I say rockstars should take back the spotlight.
It didn't get any responses, so I thought it might be worth posting here.
go jam out some old cherub rock solo or something!