It would benefit the single day guests that only have a single shot at experiencing Hagrid. Right now, the queue is bombarded with hotel express pass, regular express pass holders and to top it off premier passholders after 4PM.
IMO, limiting the # of users coming in through the express line should be a priority to reduce impacts to standby lines. Hotel guests already get an advantage by having access during early park admission.
I would remove Express Pass entirely and create a new system just for Hagrid that would be an additional upcharge just like Disney's lightning lane system*. This might be a bit too much, but at the very least I'd remove it from premier annual passes. Hagrid is too popular to prioritize passholders who can visit often versus the 1 day guest.
This chart just shows you how bad it's gotten... (thanks to Thrill-Data.com)
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