It sounds like you have been before, and this family had not. So even if you both "winged it", you, as a long time member of this board likely know some strategies for making the most of your day at a busy time. And, in my opinion, the week before Thanksgiving was pretty busy (we were there, too). I would have been very overwhelmed if I hadn't prepared in advance via reading here.
Also, even if they DID use
Genie+, there was plenty of room for frustration and dissatisfaction with that on Thanksgiving week. Most afternoons had very limited availability at most parks, and many casual visitors likely didn't know that it was important to book as soon as they were eligible (if they even knew when they'd be eligible).