I would bet money, blocking this to only Park reservation people is avoiding swamping their system via non- eligible people (from home)
It never made sense to let anyone in the app front door, only to reject you if you are not in the park, on step 2 or 3.
Yea I get that they ultimately reject you if not in the park, but it's much better to block folks on Step 1, than allow that much App/IT traffic everyday at 10am to flood their system.
Smaller subset of folks early in the day will help. The problem moves to 7am , but - I'm in favor of this change as 1st step mitigation.
I preferred December '19 getting up at 5am to get the best chance...but I'm glad they are tweaking the system.
I remember reading about guest surveys a few weeks ago - they seem to be listening.