I'm going to have to say there is a time and place for everything. I think the biggest factor here is unwelcome kilt lifts, and especially unexpected ones.

If someone (of either gender) lifts your kilt, that is unwelcome and something needs to be done about it.

If, however, I am in a relaxed environment and a young lady playfully asks about what's under the kilt, that's an entirely different circumstance for me.

This sort of advance is just like any other, it depends on the circumstances. For instance, I wouldn't want just anyone walking up to me and giving me a hug either.