Textbook invalidation: "Your experience of being an incel due to physical or mental reasons isn't demonstrable in any way."
While "sexual gratification" isn't the exact term I would have used here, it's pretty obvious the original commenter meant finding a sexual or romantic partner. He clearly wasn't referring to something that can be achieved through masturbation.
The existence of a large demographic of incels is the demonstration of the premise. If dating were a matter of "anyone can find someone," incels would not exist. Look at communities designated for femcels or lonely, single women. Even in those spaces, where women complain about being alone and wanting a partner, there is virtually zero interest or willingness to date the men in incel spaces. When even the most desperate segments of the female population completely reject a specific group of men and promote prejudiced views about them, it's proof that incels are unable to meet the baseline of what women find attractive. Besides, it is obvious that women are vastly more selective than men when choosing a sexual or romantic partner.
The negative mental health effects of involuntary celibacy are well-documented by research on incels, which, of course, IncelTears refuses to acknowledge.
There is no evidence that incels who have shared photos are representative of all incels. And not all of them are good looking either; it's just that IT wants to cherry pick the examples of incels who shared their pictures and turned out to be good looking.
Their claim that hypergamy, as in women dating up in income or economic class, is not occurring is also completely false and easily disproven by research.