You are one of the most savvy soccer observers I "know" (in that anonymous sort of way) but having watched a ton of Cal games for the last decade and, most relevantly, the last two years, I'd say that this year's D is a direct result of having an excellent GK. In 2017, they had Boyd in goal + 3 seniors on the back to go with their excellent frosh center back (who has had a great year this year and did great in particular v UCLA) and 1 of those seniors on the back was an all-American. They had a good season and had a fluke 1 min in to Round 1 v SCU when that all-American drew a red card, SCU hit a perfect free kick and that was that. Last year, they had Smith as a soph but no seasoned D and an inexperienced GK and the team struggled. This year, the team is largely the same as last except AA in goal - the D IS better as a unit and AA is a big reason for that (I'm partial to GKs and their impact on the team). I'd even say that that the D, not the GK directly, was what won that game at UCLA but it was their confidence in their keeper that allowed them to take the chances. She's made THE difference. (as for the Stanford game, I'd say that the GK was the reason it was 4-0 and not 10-0. 13 saves, 39 shots faced, 17 shots on goal. Most notably, Marcario had a whopping 6(!) shots on goal and scored exactly zero goals. Yup, Cal's GK was a difference-maker in that game. Did not give them the win and did allow 4 goals but played a hell of a game)
All that said, it is a fun part of sports that we can have this type of discussion about excellent players. It is not me saying Fishel is not excellent nor you saying that Anderson is not. We are talking about the margins of excellent, excellent players, and it is a tiny # of players that can be part of that discussion. And that's fun. My kid joins the fun directly next year and I can't wait to see more of these players in person.