To say most places seems like an exaggeration. As someone who loves ordering food online, I hate not being able to pre-order a meal. That said, Disney's mobile order is available only at select quick serve type locations.
I will say that, in general, mobile ordering was seen as a gimmicky service for restaurants that a lot of people really didn't care to use or really didn't care about in general. Now, mobile ordering has become rather essential for our new normal. Being able to pre-order your food and have it ready to pickup or delivered is really important now, and it is nice to see these previously gimmicky tech upgrades really become useful and a necessity. I only hope that mobile ordering in general really does evolve and become the standard, best option for obtaining food.