i’m in the US, if you took a call for more than a few mins a busy metro car I’d tell you to knock it off

People talk on the phone all the time on every US metro I’ve tried. Seems fine if they’re not on speaker or raising their voice

My dad speaks loudly on speakerphone phones in restaurants and public spaces daily because he's a rude old asshole.

No one beside myself has ever told him to stop because I think being old gives one a bit of a 'get out of jail free card ' with regard to social behaviors.

I would love for you or someone like you to happen upon him and tell him to knock it off, but alas that seems fleetingly rare.

Unfortunately, these days, most of us won't do that because there is a high likelihood it could incite violence.