It depends on expectations. But well, there are a lot of bombers. In my case, the "possible" smut came out as a lore heavy and slow slice of life story with a "bait" title so it got lotsa of onestars quickly, sometimes 5 during one night over trending. But there are also people who just do it because they can. After I posted my second story, it looked like some jumped ship and transferred their ratings instantly.
So, it's not exactly about smut I'd say, but it has higher chances to get bombed. And once you are branded, you are pretty much done. Some people drop onestars just because something is not up to their liking, like the premise or something. I completely expected getting blasted for having brothel in the title so I wasn't surprised. I actually was expecting more since I'm touching a lot of sensitive subjects now and in the future, sneaking them into the story.
Anyway, it really depends on the situation. I've seen many "normal" stories getting blasted too while they were decent. And naturally, most of onestarring happens during you getting to trending since the usual onestarrers are too lazy to go through the catalogue of novels and it's just a daily thing for them to drop some on the front page.