I don't see anything in the concept art for the hub that resembles nightlife though. There doesn't seem to be space there for the type/size of nightclub that would be appropriate for a massive theme park with the throughput of Universal. And while Universal don't have dry parks - I'm not sure a full bar is something they'd go for. There's a difference between a bar and offering a beer with a meal.
Outside of bars/nightclubs what nightlife would there be?
CW and Disney Springs are both 'late night', with most shops/restaurants closing at 12am on weekends, and other activities staying open even later (concerts/clubs/bars until 1 or 2).
Guests might see a late night movie and leave Disney Springs or CW in the early morning. (Book a midnight movie and see what time it is when you walk out.)
Late night activities could include live music/concerts/performances, comedy clubs, shopping, restaurants, escape rooms, vr experiences/arcade, movie theater, bowling, mini golf...
And rides.
Same kind of stuff you find at CW, Disney Springs, or other entertainment around Orlando including ICON. The ICON wheel stays open until 12, Starflyer closes at 2am, Escape Game Orlando until 11:45... Pretty much everywhere aside from the theme parks themselves stay open for tourists late night. (Again, it's all about profit. A park guest already paid earlier in the day, after a while you stop earning money from them.)
We have no idea what's inside the buildings, how many floors each building is, or what might be omitted from the concept art. Earlier this thread I suggested the larger building at the front could be a Cinemark theater... I've heard speculation that one of the buildings across from the dueling coaster looks like a Hard Rock Cafe (I disagree but that's besides the point).
We simply don't know what's going where. But there's definitely space.
Additionally I can't imagine hotel guests to be delighted with guests still in the park at 2/3 AM.
Pretty sure the rooms will have good sound proof glass. Guests hopefully know what they're getting into when they book this hotel... Hotels around the world are surrounded by late night entertainment so this is far from being unprecedented.
Hotels including Wyndham and Fairfield are just as far from the Starflyer (again, 2am) as a EU hotel would be from any outdoor rides UOR might keep open.
I mean, if there was actually an issue with this, then EU would essentially need a curfew. UOR could never hold any late night event here including after dark tickets, Halloween events, AP appreciation night, corporate events, concerts, etc. If that's the case, cancel this hotel right now.