Well, that seems to be the policy solution that Japan picked. In addition to the cultural development of well-intentioned men holding their hands in the air on crowded mass-transit to prove their good intentions, and thus throwing suspicion on men who don't do the same.

Though it's worth noting that mass-transit in Japan is frequently packed so tight that if you don't have your hands up, you're literally touching someone else anyway. Not hard to see how that amplifies the molestation problem significantly in Japan even if other countries (presumably) have the same % of men with a propensity towards such actions.

It’s not suggested as a ‘solution’. It’s an ‘option’ some of us women would like...that’s all.

Apparently segregation is the new answer, according to progressives on HackerNews.