4 hours is an awfully big investment... Especially for those of us with multiple young kids and who no longer own their own free time. Care to give the gist?
There are a few older shorter videos in the half hour range, I highly recommend checking them out if you find some quiet time! (It's awfully hard for me too in recent times, I haven't gotten around to watch the Living Characters one myself, so I can't give the gist... I'm just glad I got the holidays off to finally catch up!)
https://youtube.com/watch?v=T0CpOYZZZW4
She covers everything - the line getting in to the hotel, the size + cost of the rooms in comparison with the same size/cost on a Disney cruise ship, and theories on why the experience was so poor.
For example, the working WALL-E robot that's made a handful of PR appearances weighs seven hundred pounds. They absolutely can't risk that ever running across some kid's foot.
imagine it packing a kid into cube
gkoberger's peer comment is a pretty good summary. Another interesting point is that these technologies can benefit the brand bottom-line even when they don't make it into the park, because part of Disney's brand is "tomorrow today." Even when things are one-offs, they become one-offs that people stitch into the legend of the parks (in both the retelling and in their own memories), which gives them a larger-than-life feel; your visit might not include one of the "living characters," and statistically it probably won't.
... but it might. And if it does, you'll never forget it.
Personal anecdote / example: I stopped in at the "droid factory" in the Star Wars: Galaxy's Edge area of Disney World a few years back. They had several bits of merch for sale including one life-size R2-D2, inert. I took a close look at the R2 because it was an impressive bit of work. Turned around to look at a rack of t-shirts. And was, therefore, startled as hell to hear a bwoop behind me, turn around, and see that it had followed me out of its charging receptacle and was staring at me. It was not at all inert; it was a very impressive operational remote-control replica.
The cast member behind the counter was doing his best to hold down his grin and not give me a "GOTCHA" look. He has to, because you never know what kids might be watching and he doesn't want to break the magic. And... Yeah, he got me good. "That time I was at Disney World and R2-D2 followed me around the t-shirt shop" is gonna stick with me.
Totally get it's difficult to make time with kids, but depending on your kids ages... the video shows a LOT of Disney characters talking and doing things and the videos are colorful, so it could work as something you can listen to and they won't mind having play in the background!