Why are there so few female taxi drivers?

That would be seen as less risky for sure. Might even be less risky in practice.

Rape.

What kind of racist ass shit is this?

The kind that are able (and often do) accommodate multiple people, including possibly a bunch of guys? I'm not sure what your question is trying to ask, do you think a group of men taking a taxi is a particularly odd thing?

Or imagine if half of the people around you were the size of The Rock by comparison 😳

I thought their meaning was obvious. In the places you've paid any attention to the sex of the taxi drivers, any would-be female taxi drivers have been deterred or driven out of the job by too much harassment.

Not just that, but you'll also experience a good deal of social pressure from your friends and family, or future co-workers. Some can be of the patently ridiculous variety, like "Oh, that's a man's job, why would you want to try and do that?" but you also get some that can be well-meaning and grounded somewhat in reality, like the potential risk for violence and/or sexual violence that a female cab driver would be perceived as more exposed to. These can be mitigated to an extent, if you find the right niche to go into. For example, I would think the risk for violence would be lower if you were just doing airport runs, or medical transport for the elderly, rather than being the late night driver picking people up from clubs and bars to bring them to their private residences.

For a job that has an old boy's club formed, a new, female employee can also often expect to have to deal with regular harassment, whether it's old-fashioned, paternalistic sexism, or active efforts to drive away women that the men working there view as encroaching on their private domain. I'm not excusing this behavior or saying it's something women should put up with, but that is the simple reality of many career fields society views as "men's work," and knowing this in advance will often discourage women from even trying to get a job in these fields, absent credible signs that the company they're considering is making substantial and concrete efforts to change this culture and make the work place not be misogynistic, or some other pressing urge (i.e. "I can't get a job somewhere else where I live that will pay my bills and avoid homelessness and starvation, so I guess I'll put up with the harassment and misogyny until I can move elsewhere or something better opens up.") that means they're willing to overlook it. Rather perversely, the men who see women leave the job in short order due to the men's behavior, rather than the actual work or work-related conditions, often take it as confirmation that women aren't cut out for that line of work. Meanwhile, those women who persevere, but don't take shit from their male coworkers and dare to make them actually face consequences for their own words and actions will frequently be maligned as "bitches" and socially isolated at work.

It's hardly surprising women don't actively seek out to subject themselves to such conditions on a regular basis, absent some external influence that either seeks to ameliorate the hostile environment they face, or else compels them to tolerate it as the least terrible option available.

Wait, have you never heard any of the Boomer jokes about "women drivers"?