Your 'bad decision' day does let you get on five rides, and this is achieveable as a solo adult, or a group who entirely follow the group plan unwaveringly.
This is not the only demographic in the park. A family with smaller, and older kids, for example, is going to have different priorities.
You didn't see any shows, or main street entertainment. You only grabbed a quick service bite to eat, rather than finding somewhere to sit and ordering food for everyone, and then having kids that take a while to eat their lunch (And certainly not wanting to waste it because it cost you the GDP of a small african nation). You didn't get photos with any of the kid's favourite characters, you didn't browse the giftshop so your kid could spend the $10 Grammy gave him on the small piece of plastic crap that is all he can afford...
And TOILETS. You haven't allowed a single moment for the umpteenth trip to the toilet because Sally's bladder isn't bottomless and the bottomless sipper is.
I can't really be bothered going through a hypothetical analysis on the queue wait times and what not, but if you throw in 'wanting to go to the toilet' and 'wanting a snack' and 'need another drink' and 'can we get a photo', as well as trying to herd the 16 cats that make up your family, I can assure you, 3 rides in a day with a family of mixed age kids isn't outside the realm of possibility. Especially if the kids age groups mean that a trip to WB Kids is necessary so the little guy can ride something too (sure families can split up to do things like that simultaneous but not all families want to do that).
Can others do more? Yes. Does that mean the 3-rides in a day reviews are bullshit? No. We've long talked about guests in general leaving their brains at the door. they're on holidays. they don't walk into the park with a game plan... and they shouldn't have to.
I think I covered this, but just to be clear, you seem to be discussing a single person's experience in the park (And I agree, probably only one person who wants to do both) but in the scheme, Dad, maybe Mum, definitely Teen are heading for Rivals, but early primary schooler wants to do JDS, so as a unit, that family wants to do both, and therefore has to line up for both.
Yeah, the teen is probably going to go off on their own (these days they've got phones) but Dad and maybe Mum probably want to ride Rivals too - and someone has to look after Jimmy who isn't tall enough to ride yet.