*BINGO* goes to ScottB for correctly identifying the major reasons USAir's former PSA routes in the California Corridor collapsed - Delays on the East Coast cascaded into the West Coast system due to the way USAir routed the planes. USAir's way of doing business was even more expensive, which meant the airline lost even more money out west ...
For the passenger used to decades of reliable, frequent service, no one wanted to hear they had to wait an extra hour for the next flight due to snow in Dayton, Pittsburgh, etc.
But let's not give too much credit to Southwest for USAir's decisions regarding the market. The way people flew up and down the coast was radically changed in the late 80s/early 90s. USAir was already beginning to pull back flights and close stations before Southwest became a real presence, with all of USAir's service in/out of Oakland ending in May 1991, the same month Southwest started to fly LAX
to expand beyond their single route of SFO
in the state. Southwest merely pulled into a vacuum and fought head-to-head against the one remaining major player, United, who had begun competing head on with them by adding routes such as OAK
with frequent service and low fares, which was short-lived. Continental had previously attempted to invade American's turf at SJC
by running DC-9s LAX
for $39 (with some flights continuing onto SEA
), which lasted barely a year, if that. During this period America West began running intrastate flights (long ago abandoned), and Alaska was beginning their slow but deep expansion in the lower 48. Throw into the mix that Delta was shedding former Western routes, and American was dropping former AirCal routes. What a mess.
A long tradition of easy, inexpensive flying came to an end. Lacking interline agreements, you can't take your Southwest ticket over to another airline if your flight is running late, as often happened without question regardless of the fare you paid between PSA and AirCal. (Anyone else remember that tickets from PSA's self-ticketing machines were valid either way on the route purchased?)
While it's nice to dream, no one has taken over the extensive networks along the west coast offered by PSA, AirCal and Western.