Used to be the West could seriously hold its own against the Southeast (in which I include the ACC). There would be several regionals out west, at Fullerton or Long Beach or both in addition to Pac-12 teams, and of course Fullerton, Stanford, USC, Arizona, AZ State and the Molesters have won multiple titles. Not that way any more, it seems. But the Big 12 has gotten weak too. No Little Dozen team has won since Texass in 2005.
It used to be that the good players gravitated to the Southwest. The weather was such that they could play more. At one time those teams were allowed to start their seasons in January, IIRC. But then the NCAA instituted a universal start date.
The facilities race added another dimension. Those West coast powerhouses didn’t keep up. There are too many diversions in their areas for them to draw like most of the SEC. In Tempe, for example, they have pro baseball, football, and basketball in nearby Phoenix. Their college baseball team gets next to no coverage.
I think there is still good West Coast baseball. I don’t think the teams that play are viewed equally by the selection committee, but teams like UCLA, Oregon State, Fullerton and Arizona seem to play well when they make the tournament.
There is less media exposure and the geography — coupled with relatively small budgets — doesn’t create a lot of opportunities for West Coast teams to play or recruit other parts of the country. It seems like West Coast teams are kind of forgotten about until the postseason.
Many public-school D1 programs in California outside of those in the PAC-12 only offer scholarships (full or partial) based on in-state tuition rates due to program finances. Hence, those schools are hampered in recruiting out-of-state recruits. California’s natural geographic isolation from other populated areas of the country doesn’t help either.