In 2015-16, USA hockey (per their website) had registered 364,500 total players that were 18 or under. 11,680 of these were from California, or 3.2%. 2016-17 numbers don't seem to be posted yet. Per the MHR tier 1 rankings for 2016-17:
four 18U teams out of 134 -> 3.0% CA based (#27, #50, #85, #114) average performing
five 16U teams out of 147 ->3.4% CA based (#21, #43, #68, #82, #102) over performing
four 15U teams out of 80 ->5.0% CA based (#23, #29, #41, #56) over performing
three 2002 teams out of 109 ->2.8% CA based (#36, #39, #57) over performing
four 2003 teams out of 97 ->4.1% CA based (#3, #50, #60, #87) top heavy
four 2004 teams out of 92 ->4.3% CA based (#11, #15, #32, #56) high performing
three 2005 teams out of 90 ->3.3% CA based (#6, #15, #55) high performing
The numbers suggest California tends to be slightly over represented, while demonstrating the quality to back it up. CAHA deserves at least some credit for that. But it would seem there may be a little more room at a birthyear or two for perhaps one more AAA team, if the talent is available, ready, and willing. Part of the problem may be that 1/3 of that remaining marginal AAA talent is in Norcal and 2/3 in Socal...maybe they could practice and play out of Bakersfield.