I agree with you that getting directly admitted to CS has been harder than I expect. My son is like yours in that he takes his waitlist and reject in stride and goes back to his video game while I’m more nervous and anxious.
He wants to double major in CS and Music but applying direct to Music is not easy either due to audition and portfolio requirements more suited to a performance major than a music tech specialty (my son’s interest), so we researched places that offer both in a combined major and found a bunch of CS/Music combo programs out-of-state. UCSD is the only UC that offers something similar with their ICAM major so for all other UC’s, Cal Poly and SJSU, he applied CS only.
He was accepted CS to UCSB, UCSC, Cal Poly and SJSU and waitlisted by all the other UCs so far except Riverside & Merced (he didn’t apply there). My surprise is that he has been admitted to all CS/Music combo programs so far but they are all OOS, even from reach schools like UT Austin and UIUC, so while I have been told that UC results are very hard to predict and seem almost random when just looking at stats, I do think in my son’s case, applying to CS is a key reason why he is on so many UC waitlists but accepted elsewhere OOS.
I think there will be movement in the CS waitlists since there are so many really accomplished kids who have received multiple offers and they can only attend one college, but it will take time to cascade down. I suspect yield predictions may be a bit off this year with the explosion in apps from a slightly declining pool of total applicants. We are still waiting for a few more that will all roll in before April 1. I really want him to stay in California, so I’m planning to drive down with him over Spring Break to visit Cal Poly, UCSC and UCSB, even if we can’t enter buildings, so that we can just get a feel of the campus and the neighborhood. We will decline offers as soon as he can narrow down more choices. He already declined CU Boulder, UT Austin and Northeastern and will most likely decline UW in the next day or so.
It’s great that your son knows exactly what he wants to do and it sounds like his work ethic will carry him far. Kids are more resilient than we parents sometimes give them credit for and I have a feeling that he will get into a place where he will thrive and succeed. Sending you best wishes for his remaining decisions!