SFO: Why the need to pick up at departures?

There is no room for TNC at arrivals. SFO has a strict system in place for all vehicles picking up or dropping off there. Airport staff will also instruct pax to go up to arrivals.

I'm confused, did you meant to say airport staff will instruct pax to go up to departures, or is your point that airport staff are telling them to go to the wrong place according to what Lyft has apparently been told by the airport...?

The airport has very specific signs saying "Uber, Lyft pickups at Departures".

I have no idea why.

Way way easier to spot and pick someone upstairs. I travel a ton and have always had friends/family pick me up in Departures unless I had luggage (which was rare).

I will say this... My gf picked me up on Sunday at SFO departures and I swear every 2 feet there was someone who looked like they were waiting on a pick up. It's getting annoying too when you get dropped off the Departures section is starting to get full on the sidewalks with Uber/Lyft pax. Two years ago it was empty.

Maybe it's because they don't want problems between Uber/Lyft drivers and registered taxi drivers.

Yes I think they're trying to avoid that. It is just turned SFO into a much harder place to get picked up.