Other questions have been asked about riding public transportation in close proximity with persons of the opposite sex. It was cited that Rav Moshe Feinstein, zt'l, permitted men to ride on crowded subway cars in close proximity with women even though it might entail actual touching.
Currently, there has been conflict on airplanes and buses where men have asked women to change their seats, or have asked others to exchange seats so as not to sit next to a woman. Given that these persons are relying on a psak halacha by some gadol, I am curious as to how those decisions distinguish Rav Feinstein's reasoning.