Personally, based on what I’ve seen, I think the number in CA is FAR higher than 20-23%. My office about 15 years ago was adjacent to a huge condominium construction site and it looked like 100% of the workforce was minority, mostly Mexican (but probably other Central American workers, too). How many are illegals? Half?
Look at the percentage of illegals, in CA, and, that will get you closer to the actual number of illegal workers.