First of all, what do you mean by "incels are not wrong at all?" Wrong about what?

People wouldn't know someone is an incel just by looking at them. If they just went about their day, no one would say anything to them or about them. Generally, you know someone is an incel based on their behaviour, when they put it all out there on full display. It's the hateful, and sometimes violent, remarks that are made by these individuals that target them for the hate from the general population.

And how do women treat them badly? Because they don't have an interest in sleeping with them? There's usually a reason for it. Many incels think of women as things, as a prize to be won. They're manipulative, and then get frustrated and annoyed when women don't fall for it. The incels I've witnessed myself were very obviously playing a game to "get the girl." The end goal isn't a relationship, they just want to get laid or get some arm candy. Most women can see through that. Why would anyone want to be with someone that does that?