“..way back in europe/russia/spain/poland/italy etc. No mechitzas existed..”
Really? Maybe they didn’t daven or learn then eaither? Care to recall the story of the Satmar Rav when he was in Europe? – How someone was grinded in his own grinding plant, because he didn’t listen to the Rav’s warnings about having a Mechitza.
That’s the slippery slope path of the evolutionists… in the early days they didn’t keep the Torah, now we evolved into a nation that keeps HaShem’s mitzvohs…