Ironically the prudish attitude to male standards in the USA has a lot to do with SJWism and cancel culture.
America and maybe to an extent western society is more prudish today in some ways than in the past. I digress with the more popular opinion here.
I would say it goes back even further than SJW-ism. The US is always slow to change popular opinion. If anything SJW's would be for it. But they would think something like it is only for gay men or something. (because they are actually closed minded)
Cancel culture has always existed it just never really had a name till now.
The thing is the stigma. The thought that men wearing thongs is taboo. I think it has to do with sexuality and sexual preference. I also think that a "standard" man is a really silly concept. It is almost like asking if there is a "standard" woman. If you follow any of the studies about attractiveness everything boils down to really basic primal needs. Women have to be children oriented and men have to be providers. When it comes to looks, different regions have different beauty standards. Both the realationship needs and the beauty standards form the popular opinion.
The thing about the US is that we have so many different sub cultures and are the only country in history to experiment with true freedom. I think the largest issue is not being taught about freedom in school. The actual underpinnings of our nation. Freedom is something you have to fight for because once it is gone it is gone forever.
Anyhow, we are free to express ourselves and wear thongs as men. Others are also free to be objective to that. The clash of freedom then questions the morality of how much skin is appropriate to show at the beach. Well I would say there should not be different standards for men than there are for women. And that is how most beaches are.
The problem are assholes. People that want to force their idea of modesty on other people. That goes against freedom and is exactly what schools do not teach. When it comes to regulation, like minded people tend to live together. That is why states and cities have their own laws. It is horrible that you have to travel in order to be around or live with like minded people. But it is one of the freedoms that we have in the states as well. That is why I would never move to a place like colorado or california. Both beautiful places but the politics differ from my morals. Which is a bit sad because san diego is a very man thong friendly place... I guess florida will just have to do for me.