California is sort of the hot bed for club teams. UCLA has a pretty famous club team that has some cache as part of their program to work your way onto real team. A few guys have moved from club team and made an impact in their bullpen. As college baseball has grown, the impact has dramatically lessened. Kids just go elsewhere.
It's sort of their version of the walk-on program at Nebraska football.
To me, I cannot imagine doing that when I could go Juco. In Juco, the scholarships are full-rides and then you can get a D1 offer a lot easier than the portal now because they are setup to do so. They have heavily attended scout days where you get real exposure and they're earlier in the year so D1 teams aren't in full-steam mode yet.
If I were a fringe P4 guy, I'm leaving after my freshman year with P4 on my resume, going to Juco to get playing time to get stats and eyes-on, no debt, then transferring to a high G5 or a P4 with an opening at my spot.