To add insult to injury, the Star Trek "pairings" tended to be super hot women with weird looking alien "males". DS9 took it to extremes.
I don't think the reverse was seen much at all.
That wasn't just on Trek.
It happened all the time on other tv shows and movies so much that it has become a trope. It is especially common on comedies with the dumb average looking husband and the hot wife.
It's stupid enough when other shows do it. But Trek doing the same irks me to no end. Particularly because of what's already been mentioned about alien races being compatible with humans, but the mere idea that alien males would find human women to be desirable. A bull doesn't desire a human woman, it desires a cow. A rooster desires a hen.
A ferengi should find human women revolting, as we know they find humans in general hideous. Yet we see Ferengi in TNG and DS9 actively seeking the hottest human females they can get. To what end?