I couldn't agree more w/ ClaraOswald.
Calling it a "huge PITA" is your opinion. We don't share that opinion and that's perfectly fine, but you can't assume everyone agrees with it, either. Though it's funny we're both vets who've kind of "switched sides" in terms of those opinions. I used to think WDW park hopping was difficult in my DLR-is-the-world days.
As Clara said, you are certainly loudly implying that other that don't share your view are wrong.
I don't know if it's true, but you certainly speak like someone who doesn't have children. Trucking around strollers, packages and managing children is not easy even when your children are capable of managing themselves and helping, but when they aren't, it's quite another proposition. They may both be matters of opinion as is the ridiculous question people ask daily about "worth", but you're telling people that their opinions are not correct, or at least you are couching them in words that imply it whether you realize it or not.
You don't need to rely on FP+ and you certaintly don't need to schedule your ADRs six months out. Those are also myths. Last-minute trips are easily possible, and so are last-minute ADRs. That's exactly how we do WDW. Just because 7DMT, FEA, and CRT are hard to get doesn't mean there isn't a lot of flexibility left. There definitely is. If you're tired of planning your WDW trip six months in advance, then just don't do it that way anymore. We don't, and we still manage to ride what we want and eat where we want, and we visit at busy times.
You sure like that word "myth". Let's define it: a widely held but false belief or idea. You are again, telling people their beliefs are patently false. Again, in YOUR life they may be untrue, but that's not a hard and fast truth and it only applies to you for sure. ALL ADRS don't need to be scheduled, but many most certainly do. If you want to dine at certain restaurants, you most definitely need to make your ADRs as far in advance as possible if you A; want to have a choice in what time you go, and B: if you want to KNOW you'll be dining there for certain. That is a pretty verifiable fact, not myth. Call today and see if you can get an ADR for Cinderella's castle breakfast tomorrow when they open. If when and where you dine isn't a big deal then great for you. If I want to dine at (ugh, I hate their food but since ADRs are hard to get, I'll use it as an example) Chef Mickeys, and you want to do it when they open so you can hit the parks, then you DO need to schedule it far out (unless you get lucky and grab a canceled ADR). I for one, don't want to go to a park, have to leave it to get to the CR, eat, and then go back through security and turn styles to the park again to resume my touring. Not only is that hugely inconvenient, it's exhausting and a big time suck. Think about times where the parks aren't open until the wee hours of the morning. Not all days and times of the year are created equal. Some days are significantly shorter than others so one has to manage their time more efficiently.
I come at WDW from the perspective of a DLR vet who loves flexibility, and I really think it's there if you let yourself find it. It's so easy to get wrapped up on the WDW side of these boards in the discussions of people flipping out that they didn't get that one FP+ or that one ADR that they think will make or break their trip. The moment you decide not getting a single ride or restaurant reservation isn't the end of the world, WDW gets so, so much easier and more flexible. It just opens right up in a similar way to DLR.
And for fullest disclosure, I'm essentially an adult child on the spectrum, and rigidity drives me crazy in a really bad way. I never feel trapped without alternatives at WDW, even without 180-day planning. Our trips, at most, are planned a month out. Over Pop Warner this month, we didn't event make some FP+ reservations until a week out, and managed to get a same-day (actually, same-evening) ADR for the restaurant of our choice at Epcot. If we believed the hype about 180 days out, we'd never visit WDW. But in our experience, it's just never been a limitation.
You sure do assume much about the needs and desires of others. You can love flexibility, sure, but you're going to have to be flexible to dine wherever you can walk in or get an ADR at a late date then. For someone that goes regularly, that's pretty easy as you can just catch something else next time, or perhaps, you've done that venue a lot and just don't care anymore. By not booking ADRs well in advance for the most popular venues, that's what is happening. You are going to be at the mercy of whatever might be left a month or so out as you say you like to plan. That's not the case for most visitors to WDW.
I'm quite capable of making mature and objective assessments of what is and is not possible for me and my family and I'm quite beyond letting others on BBs influence my POV. I rarely come to this board (or any boards) anymore. I was planning my WDW trips before the internet existed. No one tells me what I should and should not worry about. I know what my family likes and wants. Period.
For you, an adult on the spectrum as you say, that's great. You've had a lifetime of learning how to cope. But, you're only 1 person and as they say, you've met one person on the spectrum, you've met ONE person on the spectrum. People w/ ASD share some similarities but they are all miles from each others and quite frankly, an adult w/ ASD is miles different from a child, and in my case, a 9 Y.O. child w/ it. I'm glad you've learned how to make things work for you, but please don't tell me that I'm being rigid in not "looking for flexibility" when I've been traveling to WDW mostly every other year (sometimes 3 or 4 years between in a few cases when we were having our children) that I don't know what to do and how to find it. You DO have to schedule things far out if there are certain things you want. The popular things. That's just how life is in the #1 tourist spot on the planet. Please feel free to give your opinions, but please do not presume to know what works for everyone in the majority of situations.
I'll just add as a final note to my opinions and thoughts that I fully expected to not like DLR even half as much as I did WDW. While my love of WDW has gone down over the last decade we STILL planned on retiring to FL in 10 years. Where we moved was and still is directly related to how far we'll be from The Mouse. We didn't even try to go to DLR until this year because we simply had no desire to. Only because of the increase in the need for hyper-planning to enjoy the resort like WE want to enjoy it did we finally decide to give DLR a shot. That and our oldest is in 11th grade and taking him out of school for the 9-13 days we used to at WDW just wasn't prudent but we cannot travel in peak times. That I have changed my mind on which resort I love more was a complete surprise to me.