Solution 1:

If you really feel the need for a pejorative, what's wrong with just saying their taste is "shit"?

If you really want to come up with something that has some sting, a non-pejorative term that actually attacks a feature of the music will probably serve much better. Which do you think burns the most:

Oasis is gay

Oasis's tired regurgitation to the tropes of Lennon and McCartney without any of the wit, originality or heart the Beatles had are why the Gallaghers are the most boring performers in the history or rock music?

The second has no such slurs, but I would say it was a more powerful attack.

But I also understand the need for just dismissing something quickly, and shit serves fine without piggy-backing on the oppression of any group.

Solution 2:

No is the short answer. But his type of rebuke always requires shock-value and people are continuously inventing new ways to shock as the old ways lose effect. Your desire for a word that is not offensive to someone but can be used to express contempt cannot be met. [You have been challenged.)]

So, the use of 'gay' in this context will not disappear entirely until it is replaced by something equally vile, but different.

Previous to 'gay' the equally ugly 'lame' was used until its shock value wore off. Lame is a reference to disability and the disabled should not be mocked. The Nice police on this site should be in touch with you if you use it inappropriately and you were unknowingly unkind in your youth.

'Dumb' preceded lame, I think. It's effect comes from a belief, now dispelled, that people who could not speak were stupid. The next shock-word will also be offensive, probably to some minority.

Solution 3:

Nowadays I think most people will immediately to jump to one of these alternatives, if not using the old-fashioned and homophobia-charged "X is gay":

  • X sucks.
  • X is shit.
  • X is wack.
  • X is weak.
  • X is garbage/trash/some other word of disgust.
  • X is the worst.

These can all be elevated in disgust by using an expletive exclamation. For example:

  • X fuckin' sucks.
  • X is fuckin' shit.

Good old escalating or emphasis terms work, too:

  • X is utter shit.