You’re at least living here now, though, and have been for a while. That’s a way different thing than someone that grew up in MontCo, mayyyybe went to college here with no intention on staying, and then moved back saying they’re from Philly.

I didn’t grow up here, and I moved around the country a bit after college, but I’ve been here as long as I’ve been anywhere and don’t plan to leave.

Where else would I say I’m from? The town I haven’t lived in for 20+ years and never will again? The only conceivable reason to do that is if the person is very obviously asking where I’m “from” as shorthand for “where did you live as a child?”.

Like, if I’m in a bar in Philly and someone asks if I’m from here, I tell them I grew up down the shore in South Jersey, but moved here after grad school, because I’m not sure which version of the question they’re asking.

But if I’m somewhere I needed an airplane to get to and someone asks where I’m visiting from, where I lived when I was 11 isn’t relevant, and I’m from Philadelphia.

Though I’d agree that the audience matters. If “Philly” barely means anything to the person you’re saying it to, it really doesn’t matter if you say you’re from Philly or “just outside” Philly. You should say “just outside”, but the person you’re saying it doesn’t care and neither do I, really.