Never before could a woman open an app and literally have hundreds of men at her door within minutes (all while men struggle to get a single match). This has created such an imbalance that the women are able to reject roughly the bottom 80% of men leaving most men struggling to get the attention of the bottom 20% of women.
And yes, there are lots of men with shortcomings, physical ones, that have rendered them out of the modern dating pool whereas in the past they would have met an equivalent woman. That's no longer the case as that equivalent woman can demand a much higher quality man -- there's an unlimited supply of men to pick from.
The dating market for men has become extremely difficult over the last few years (lots of factors for that), more and more men are unable to find a mate. Men are less inviting of other men from my observation as they are in deep competition with each other -- why risk having another man around when he might take your girl or reduce your chances? Apps, dating sites, clubs, and events are filled with men looking for women, don't expect them to be cooperative with you, you are their compitition.
I believe this is a factor in men becoming less cooperative.
Young white males can easily fuck attractive girls there. That's it.