It's very minimally important, the odds of me looking at a hot dancer and then seeing she has bad nails and changing my mind about her are almost zero. And the odds of nice nails generating interest in otherwise unremarkable girl are also zero.
But, I do make some snap judgements about girls personalities based on them. I rarely like the personality of the girls with long ass nails, or ones with trinkets or other bric-a-brac on them. Those girls are often bratty and entitled and are overly concerned about appearances. I prefer the personalities of girls with more normal looking sizes with normal paint jobs. They tend to have a more common sense oriented outlook.
I wouldn't call them deal breakers on their own, but combined with other stuff they might. Long nails with lots of shit, giant eyelash extensions, ridiculous extensions/wig, and an overly complicated outfit, could certainly combine to make me pass on an otherwise hot dancer if there was a decent alternative without those things.