That's not the only contradiction. Feeling entitIed means you think you are owed something just for existing, meaning you'd be unwilling to work for it or make any sacrifices for it. However, many incels try to learn social skills, work out, take steroids, and even spend thousands on facial surgeries, just in the hopes of being able to make a woman happy. That is the opposite of entitlement.
Yet, even on articles that specifically call attention to incels' efforts, the comment sections are full of "entitIement" accusations. Why?
Incels, by definition, are those judged by women to be unfit to breed. Since women are the limiting factor in reproduction, people evolved to treasure them on a primal level, giving women a powerful halo effect. Women are infallible angels. So if women are rejecting a man en masse, it couldn't be due to anything arbitrary or superficial; it must be because he's a genuinely terrible person. And if he's a terrible person, then any attempts to improve his situation must be a Machiavellian ruse to plunder what he doesn't deserve. It's practically rape!
Of course, people aren't consciously aware of any of this. So when they feel that a guy must be an irredeemable piece of shit, they just make up things to justify it. He's entitIed, he's manipulative, he's a misogynist, whatever. It doesn't have to make sense, it just has to keep the untouchable caste in their place.