Back on the original question, if attendance is down they're doing an extremely good job of hiding it.
I've typically visited WDW every year in May and September for over 25 years with the exception of 20/21/22 due to covid.
Having just come back last week the parks really did at times feel incredibly busy. A lot of this I can put down to the school groups. I've no idea whats changed but I've never seen as many school groups as I did this time. The coach parking lot by Epcot was almost full, and there were hoards of kids and teachers everywhere. To be clear this wasn't the cheerleader crowd, altho we did see those a fair bit in our first week (We were there from 6th - 27th).
One thing that was welcomed though was the 30 min early entry. Those were far quieter than the old single park EMH system, although a cranky jetlagged me got very close to biting off a cast members head when they told us Adventureland / Frontierland didn't open till park opening (a still frankly insulting and taking move that extends back to EMH, especially as even now its still not well advertised at all).
As was the norm, late morning - early evening was the busiest period but we tend to get in and out of the parks by 11am and dont come back till 5-6pm, those mid-day hours just arent worth it once you know the place like the back of your hand.
One thing that was noticable, was that despite pretty much all resorts supposedly being at capacity (something the GM of Caribbean Beach told us - thats a whole other big screwup story) the resorts all felt pretty dead. We tend to visit every resort hotel whilst we're there. AKL was probably the busiest but even then nowhere near as busy as it's been when I've stayed in the past. Caribbean Beach felt dead at times, Riviera was often a ghost town and Pop & AoA never felt anywhere close to capacity.
So I do wonder if its just a case of artificial inflation. We all know the wait times are now at their worst levels of inflation to push people to certain places, but that combined with more people presumably staying off site is the only thing that I can think of that's causing it to feel busy.
Oh also, yeah you dont need Genie+, not at all. Despite spending about half the amount of time as I normally would at the parks we had no problem getting on everything we wanted. The longest queue I waited in was 20 mins for Rise, the secon time we went on that it was a walk on. Getting into virtual queue for GoG was also easy, all four times we got into a group < 10. Don't pay for Genie+ unless you're a first timer or on a very tight schedule.