Let's assume, for the sake of argument, that this is a literal statement.
A few of us might have a single utterly crippling flaw that completely bars us from the SMP, but for most of us, I've noticed, the problem is a number of less significant flaws that might be forgivable by themselves, but in aggregate, are death. I think this statement could be useful to illustrate this point.
Say you are very skinny, and only 5% of females will date very skinny men. So if you're skinny, navigating the SMP will be hard, but not impossible. If there are 100,000 females in your local area, 5,000 will be willing to date you. However, you are also balding, and only 5% of females will date men who are balding. You're also short with a weak jaw and big eyes. That's 5 flaws. 0.05^5 = 0.0000003125, meaning only %0.00003125 of females will be willing to date you. Now let's say your local area has 100,000 single females. 100,000 * 0.0000003125 = 0.03125. That means, out of 100,000, the odds that even one of them would even consider dating you is less than 1 in 3, even assuming you have no other flaws, and you're even able to ask every last one of them out. Also, there's no guarantee this one person will stick with you forever, especially when she has so many better options.
Just looking at the numbers, you should see the root of the incel problem. One or two flaws might be fine, but too many things going wrong at once is death, and using them to excuse not putting yourself out there is reasonable and valid.
