One study of the biographies of 1004 eminent people found homosexual and bisexual people overrepresented (11 percent of the sample), especially among poets (24 percent), fiction writers (21 percent), and artists and musicians (15 percent) (Ludwig, 1995)[1]
Surely if artistic creativity was evolutionarily so advantageous it wouldn't hide itself in the least-reproducing subpopulations
[1] http://www.davidmyers.org/davidmyers/assets/Sex-Orient-9e.pd...
Because slightly more highly creative people are homosexual doesn't necessarily mean creativity isn't attractive. It could just be that homosexuals have more time to devote creative tasks due lack of childcare responsibilities.
I would say that people often aren't consciously aware of why they are exhibiting creativity. On top of that, I would guess that homosexuals value finding mates just as highly as heterosexuals, which would be at least one reason why they would exhibit creativity, consciously or unconsciously.
To illustrate, if you're looking to marry (and have kids), and you had a choice between a physically attractive but dull porno actress, and an attractive and intelligent writer (you know because she's fun to talk to and wrote a very popular book), you'd go with the porno actress?
Most porn I've seen isn't very creative, and being in a porno is not something I have on my checklist for attractive mates. I think that's true for most people. I would wager to say that the most effective form of art is the most creative, not the most sexually stimulating.