There's no such thing as "involuntarily celibate", it's just another BS term in the fanfiction-as-science narrative of the typical hacks. I've seen men on Twitter who are literally married with children get called incels, just for having the wrong political opinions or even criticizing a crappy Marvel movie!

Anyone can get a girlfriend if they lower their standards enough, so in the end it's their choice, so it cannot be involuntary. The only way someone could be an incel is if they got thrown in prison and have no way to actually meet women, or other examples like this