I've heard a professor lament a student stating that all CAD applications should work on phones.
And why is that such a lamentable idea? Modern phones have the processing power these days. Walking around a factory, building sites or a muddy field with a phone in your hand is a lot easier than walking around with a laptop. Plus modern phones have LiDAR and multiple cameras opening up for all kinds of interesting options. Frankly any CAD platform which doesn’t embrace mobile will probably fall out of favour over the next few years.
You are probably right to the extent of multimodal for some tasks or for sensor input. But redlining a 200 page set of drawings to capture as built info is still different from assembling that set of drawings in the first place. I doubt it will be all or nothing. E.g., supporting field service will require generating particular views, but I don't see engineering review meetings skimping on monitor pixels, at a cost of N laptops per hour just to assemble a meeting.
Indeed, I'm not suggesting that CAD tools go mobile only or even mobile first, just there is a lot of very practical uses for mobiles (and tablets) in the CAD (and BIM) space that shouldn't be ignored.
To your general question, I've heard a professor lament a student stating that all CAD applications should work on phones.