UW registration weren't really open to criticism or improvement ca. 2009, either. Extremely hostile to student projects that would in any way interact with the registration system.
Having been on the IT side of student registration, it's a major undertaking for the teams involved with thousands of students to be processed in a fairly short window. Downtime of any type during the registration period has a major impact so I'm not surprised that a university is being cautious with a 3rd party system connecting and potentially causing performance or downtime issues.
It's worse than that, throwing all 60k students at the registration system at the same second with no automated waitlist is a policy decision.
Registration at my school was a zero stress endeavor because those features are built in and very good in College admin software on the open market, for at least 2 decades.
What is very likely is that UW considers something about staggered enrollment "unfair" or not right for everyone, so prefers the absurd freeforall, and therefore polices any attempt to bypass that freeforall "fairness" as unacceptable.
