This is good, but why can't these firms determine when your phone and the drivers phone are far apart?

It's not unusual to call a taxi for another person. Or to make a multi-stop journey where some people get out before others. You can even send a parcel across town in a taxi.

Checking phone proximity might be helpful in some cases, but it's not a silver bullet.

GPS does not work everywhere, and not every device support BLE beacons.

I never give location permissions to any app if I can avoid it (indeed I don't even have the spyware app if I can avoid it; e.g. I use the web to order an Uber)

Too many people order Ubers for other people so it won’t work.

I don’t know why they don’t require it. Every Uber in Porto Rico uses the PIN but I’ve only had one in the mainland USA ask for it.

You need to enable it on your account.

Exactly - I believe it should be required for safety, limits shenanigans, etc. Apparently, it is required in Puerto Rico, but I don't know if drivers have to enable it themselves or if the app knows where the driver is operating. Are you saying the rider can also turn it on all the time? If so, that's good - I've only ever it seen driver's request it (all in PR, and one in mainland US, everywhere else, no PIN).

Right, YOU need to enable it. I assumed it was always up to the rider, since they're the beneficiary of it.