The percentages really don’t matter. As in the example I gave earlier, a Sphard could be in a Litvish shul of 1,000 and be the only bocher in a tallis and it’s not lo tisgodedu.
Assuring women driving is a real shittah and shouldn’t be taken lightly, but the reality is that these neighborhoods are also aware of those who mattir. You’d really have to ask a posek if it would be lo tisgogdedu. Given that HaRav Kanievsky and HaRav Shteinman both were OK with Ezras Nashim, I doubt we posken as Joseph is saying (since they obviously knew the ambulances would be driving through Williamsberg).
Joseph, if you could provide an opinion that driving through these neighborhoods as a female is assur, then I’ll accept it. The simple argument that rov yidden in those neighborhoods hold a certain way does not suffice.