I'm not against children being in signatures at WDW in general but I have never taken mine to any. I can't see it being a problem if they are well behaved and it is at an appropriate hour.
To weigh in on the technology debate: I think that if you have to pull out an electronic item, perhaps they aren't ready to be there. It doesn't bother me as a diner as I'm not likely paying attention to what you are doing at your table (unless it involves sound). But I wonder why you would take them to experience something and then hand them a screen? At that point, it's time to go, I would think. But the kids don't use electronics a lot in our house and certainly never at the dinner table. And yes, I have real children, most of whom are past the age of 7. And no, I don't think you are a horrible parent if you do it. Different people make different choices. Just offering my opinion.