Marx, we find elsewhere, like by rav amram chasida, abaya and rava who saw the am haaratzim walking together and not sinning(which i say is a very clear prediction of the argument MO makes), and dovid/batsheva…quite the opposite.
Rav nachman of breslov has a shtikel on this stirah. You raise good points, but they don’t change the way we see gedolei yisroel behave. There are a multitude of stories about gedolim jumping out of windows to avoid yichud, and the like.
On “kekeshurah”, the rishonim already say that in their time that they’re not on the level to do such things.
Have you ever seen a gadol pick up a kalah at a chasunah? Have you ever heard of anyone after chazal doing so? I haven’t. If you can find someone relying on kekeshurah at all, please tell us – you won’t find a single rishon or acharon. Not one.