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.