I think that the evidence that only the very early modern humans mated with them says something about this. Once there were lots of other modern humans to mate with the genetic exchange seems to of diminished then stopped. I think that would point to them being unattractive perhaps even troll like, if even the long hunters were not shacking up with them. Lone males generally will have sex with about anything and anybody.
Hey, I’m all for a little “Neanderthal sex”.
I personally doubt the narrative that Neantherdals were of a different species. If they were, it’s unlikely that genetic material could be exchanged.
With proper clothes and presentation, they probably weren’t that inattractive for the time they lived in.
Don’t forget the Nephilim.