I can definitely see that happening. In fact has already happened... in Bangkok, San Francisco, Berlin, Amsterdam, Honolulu ... and a zillion other places. (Sansuk Pattaya to follow?)
I've never heard a good definition of what constitutes "sleaze". Perhaps a447 you can help me out. Perhaps in our generation we needed to seek out "sleaze" as a way for compensating for our inner insecurities and our feelings of rejection and lack of acceptance by the larger (mostly) straight society?
I think the younger generation sees things a little bit differently than we... perhaps not needing this "crutch" quite as much. Maybe they have more self-esteem and feelings of self-worth and feelings of acceptance than we do/did? Not sure.
This could also account for why there seem to be far fewer young(er) sex-tourists coming to Pattaya. Without replenishment and rejuvenation, Pattaya can never boom (boom-boom?) again.
Demographics doom establishments that don't account for this change.