Well, what is a deal breaker will ofc vary from person to person, so definitely a potential one for sure.
I don't think I'd be hit with a divorce for shaving my legs once(but no point to stir up trouble when I know she does not like it) or due to a medical reason(like needing to wear compress hose). But she really doesn't like it, kind of like how I feel about smoking women.
If I had smooth legs when we first met I would like to think it would not have been a deal breaker, but who knows. On the contrary if she had been a smoker I would not have gone on a second date... Even knowing that quitting smoking is both possible and common, I would not be in a position to request that of someone I'd just met.