Kumulani

I don't see how any of this is the fault of BA. It's a 3rd party lounge, and probably 3rd party baggage handlers and check-in agent. International traffic is a tiny fraction of what's handled at SAN, and the majority of that is short-haul flights to Canada and Mexico. For sure, you make some good points about things that could have been done better, particularly the baggage delivery time. And perhaps BA should be playing a more active role in pushing those improvements at the airports it serves.

But I also have the feeling your expectations might be a little too high for an airport like this. I think people who live in places like London, LA, Sydney, etc. often get a bit spoiled by the ground experiences there. Luxurious lounges, lots of services and recognition for people with status or flying in the premium cabin, etc. That kind of stuff just can't be supported in many markets. Smaller airports like SAN are never really going to be able to fully live up to the F experience; it is what it is. And it's less about the flights mainly being "internal US flights" than it is about what the market can support; transcontinental flights within the US sometimes have a lot of premium services and amenities, whereas flights to Mexico and Canada tend to have few.

Hopefully some of the downsides of flying out of an airport that can't provide all the premium services are mitigated by other upsides such as shorter waits in the security line and quicker access to the city center. That way you can minimize your time at the airport in the first place and extend your vacation.