Pay is not the same for a variety of reasons. You have one employer, you have infinite potential friends. Pay concerns are also normalized to things like your job, your education, and experience.
If men have fewer friends then must be because they don’t know how to make new friends, they don’t put in the effort to make new friends, or they don’t have the time to make new friends.
While the latter may be a genuine concern, women are almost certainly likely to have less spare time due to the various societal requirements on them. So it’s probably a mix of the first two.
I don’t see it being a large barrier. Some men like the image of self sufficiency and don’t seek new friends. But plenty don’t. So if you’re a man desiring to make new friends I find it hard to believe that you are unable to find the opportunities.
If men have fewer friends then must be because they don’t know how to make new friends, they don’t put in the effort to make new friends, or they don’t have the time to make new friends.
While the latter may be a genuine concern, women are almost certainly likely to have less spare time due to the various societal requirements on them. So it’s probably a mix of the first two.