SuperEWR

I think it's actually the reverse, SFO is more of a connecting hub for Star Alliance but also any airline that partners with Alaska (both OW but also some one-offs like KE and SQ), while LAX is primarily O&D. Also, my guess would be that F is sold primarily to O&D customers, the number of LAX or SFO-based F customers likely substantially outweighs the number of F customers connecting from smaller airports. The difference is that LA and SoCal as a whole (given the minimal international service to other airports, there's just CI to ONT and a couple flights to SAN, all of SoCal is effectively LAX's catchment area for long-haul) has a lot more wealthy people than the Bay Area, more demand from wealthy travelers and more people of various Asian ethnicities. Though the Bay Area does well in all three of those, it's not quite SoCal. LAX is only geographically well placed for connections from Australia / New Zealand, there's backtracking involved for European and Asian connections. If you look at how the US carriers are serving the west coast, LAX is primarily O&D to top business destinations that local customers want and partner hubs. UA of course has SFO for TPAC but DL and AA are both trying to build up SEA as a TPAC hub (DL I think more successfully than AA), which wouldn't be necessary if LAX was serving that role well. SEA works well because the northwestern location is the best geography in CONUS for TPAC, SEA has good O&D corporate demand (Microsoft, Amazon, Boeing), a decently high income population, and also a lot of people of Asian descent. AC uses YVR in the same way.

I don't know enough about how ANA's management team approaches routes, but if you look at how savvy US carriers approach LAX vs other West Coast connecting hubs (and I would consider that to be UA and DL), there's actually a lot less service from them in LAX than SFO for UA and SEA for DL. On their own metal, UA serves 8 destinations in Europe (LHR, CDG, AMS, FRA, MUC, ZRH, TLV and now FCO), 12 destinations in Asia (HND, NRT, KIX, ICN, TPE, PEK, PVG, CTU, HKG, SIN, BLR) and 5 in the South Pacific (SYD, MEL, BNE, AKL, PPT), many with 777s. Compare that against their LAX long-haul network (LHR, HND, NRT, PVG, SYD, MEL), which is tiny in comparison. Far fewer destinations, frequencies and only on smaller 787s. Ignoring the fact that some of the routes (particularly the China and India ones) aren't fully back yet, Their long-haul strategy with LAX is just to serve key destinations that matter to O&D customers for corporate contracts (ideally also partner hubs), let other Star Alliance carriers pick up the slack on connecting traffic since those carriers more or less have to serve LAX from their own hubs, and cede nonstop markets that are too competitive. If you look at how UA approaches LAX-LHR vs SFO-LHR, which should both be primarily O&D given LHR is not a partner hub for UA and SFO is the second worst place to connect to LHR in UA's network after LAX, UA has way more seats on SFO-LHR (summer schedule has 2 777-200s and a 787-9 for 148 Polaris seats) than LAX-LHR (2 787-9s for 96 Polaris seats) even though LAX-LHR is a bigger market, and I think it's because LAX-LHR is too competitive with all 3 US carriers and both BA/VS, while SFO is just UA from the US side. Anecdotally, the long-haul fares I've seen now living near SFO are roughly 1.5-2x what I use to pay from LAX. If NH have a limited number of F seats to sell since they're only on their 777s, it probably makes more sense to try to win in still good but less competitive markets like SFO vs LAX. Would seem to make more sense to me to have one 777 on each of LAX and SFO from NH's side, as JL does, but maybe they see roughly equal amounts of demand from the Bay Area and SoCal for premium seats overall, so 2 777s to SFO vs 3 787s to LAX works (not unrealistic given that pre-COVID, they flew to SJC in addition to SFO).

Btw, DL does the same thing for LAX (LHR and CDG in Europe, HND in Asia, and SYD, AKL and PPT in the South Pacific) vs SEA (LHR, CDG and AMS for Europe, HND, ICN, PEK, PVG and historically KIX for Asia), though less true on the South Pacific side.