A hell of a lot of that is just straight up depression, and honestly surrounding oneself with people who make your depression worse by feeding into your pathologies is a dangerous path. If someone hasn't yet committed suicide as a result of that site, someone will.
Being a bit less specific, I'd say right now it's hard for guys. Apps have shifted the goalposts in ways that the old dating sites didn't so much, partly in view of being in wider use and partly in view of being solely photo-driven. It's changed the formula. Women have always aimed to marry up socially. That's always been an option too if they're attractive enough, men are suckers in that regard, but opportunity was more limited. The dating pool they had access to still mostly contained people at their own level, and eventually they'd settle. Now, everyone's in the same pool, and that means that marrying up is a lot easier for women, especially if they're very attractive. It means the guys at the bottom of the social ladder are feeding on crumbs. What it means is that a lot of women are fighting for a small number of guys, while a lot of guys are left with nothing. It's unhealthy and will cause some big social problems, as well as an epidemic of loneliness, not just among the guys who miss out but also among the guys who figure out this shit and play the field, never having to grow up and settle down, because eventually they will get old and fat and wonder why their lives feel empty.
I'm so glad I got all that shit done in the 00s.