If CS is in the School of Engineering, then the UC’s direct admit into CS if you meet their competitive criteria. Even schools like UCSC and UCSD which admit into the University first and then into the major, will direct admit into CS.
Some schools such as UCB/UCD also offer a CS degree through the College of Letters and Sciences, where you have to take specific course requirements and maintain a specific GPA before being accepted into the CS major.
Cal States admit by major so you can get a direct admit into the CS major although some impacted CSU’s will place you in a Pre-Major with a minimum GPA for pre-req courses to get into the upper division classes (e.g. SDSU with a 2.0 GPA minimum).
The confusion comes into play when an applicant is not admitted into their 1st choice major CS but into an alternate major or undeclared. Then trying to change majors becomes almost impossible at some schools.