We are not living in 1950s America where people are simply uneducated and don’t know any better.
Baruch Hashem, America has become a place of Torah scholarship and we have countless very learned rabbis, who certainly are not ignorant of the Rambam you keep quoting. And yet they allow their wives to come and go as they please, and they do not instruct their talmidim to limit their wives’ and daughters’ comings and goings to “necessary” errands.
You’re comparing apples and oranges.
Find me at least one modern-day rav who says it’s a halacha for women to stay home as much as possible (and I don’t mean working vs stay at home mothering, I mean physically in the house vs out of the house regardless of her occupation). I bet you can’t.