It is, but for whom? Will the single night guests really want to start at 2? Will they know to? Or will this be the FF die-hards, who'll just marathon the houses to get their run numbers up, then continue to hang out after 6.
I'm not ungrateful for the attempt to combat lines--at least Universal is addressing the #1 complaint. But as I've alluded to in previous posts, it's going to take an overhaul of the event itself, rather than addressing crowds on the margins.
It is adding more capacity, yes.
There are *some* people who will use this additional time to stay in the park longer, as you mentioned. This might not benefit the rest of us here, but this is additional time in park the attendees will be purchasing food and drink (potentially). The added time in park, whether it benefits us or not, is huge for Universal's numbers, and is added capacity.
There may also be new attendees, who wouldn't have made a visit if not for the fact that there's now 2pm access. This is likely a smaller subset of people, again it doesn't "help" the rest of us as this actually potentially increases the queue times. But it's called added capacity regardless. When Disney or Universal adds a new attraction, the intent from their end is to bring in new people, which those new people are going to naturally go on all rides not just the new one. The only benefit to the other park guests, from a wait times perspective, is if the new attraction holds more people into that queue compared to the number of new guests coming through the gate. But regardless of this ratio, it's
called added capacity.
Finally, regarding how it benefits us from a wait times perspective... *most* people have a breaking point for how long they can stay in the park, which is far below the maximum time allowed in the park (from early entry to one hour after close). Adding park hours, whether they be early entry or not, will naturally result in many people (those earlier entry people) leaving earlier in the day, resulting in shorter lines later.
Anecdotally; I'm taking half day PTO every Thursday and will start the day (with my party of 3) at the park at 1pm. With that added 3 hours to hit HHN, I will very likely leave earlier in the night (feeling more "fulfilled" earlier than I did last year). Depending on wait times during that early entry, I may also avoid the longer, 100+ minute wait lines, especially if I got those houses done earlier in the day. Me + my two party members hitting these houses earlier and avoiding longer lines will naturally lower the wait times throughout later times of the night. That's just me, and I'm betting tons of other people (but not everyone) are in a similar boat, which should have an impact on wait times (whether it is small or not).