It isn't. When you look at studies they reveal that loneliness is very prevalent in multiple groups of people and in general. In some studies older women are the most lonely group.

Gender and Age Differences in Loneliness: Evidence for People without and with Disabilities

Gender Differences in Loneliness Over Time: A 15-Year Longitudinal Study of Men and Women in the Second Part of Life

There is much activity by anti-feminists in particular to push the narrative that men are the most lonely group and that of course the reason are women. This is heavily pushed by media because people seemingly like that idea more than that gender stereotypes targeting men are potentially more at fault.

[–] I_hate_you_welcome@feddit.nl 1 points 1 year ago

Of course, because if men ever have it bad, it’s their own fault and of course women actually have it worse. And now you know why mortality for men is so high.

[–] Katana314@lemmy.world 1 points 1 year ago

I mean, gender stereotypes still tend to be sourced by a person. It makes sense the most stretched stereotypes would come from people that don't actually fall into the demographic themselves. You wouldn't hear Mexicans claim "Oy mijo, we are all so lazy!"