Also, it is arguably dangerous to not let your teen have a phone in a time when payphones (and to a great extent landlines) no longer exist.
Payphones were mostly extinct even when I was a kid. I didn't have a cellphone either and smartphones didn't exist yet, except for the extremely rare Blackberry. But it wsn't a problem because basically every establishment around me had a landline phone I could use in an emergency. Now even landlines are extinct because just about everyone has their own phone on them at all times. Phones are easier to come by now more than ever. Kids have never been safer, even without their own phones.
Not really because nearly every adult has a phone with unlimited calling, and will allow you to make a call from their phone. I don't want my kids to be someplace where there are not some responsible adults around (drunk adults are not responsible)
Note that I agree with your point overall. My kids have phones for times when they are away and might need to contact me. I'm just saying it isn't as bad as it sounds.
Dumbphones are still a thing