[nicoburns]

That would require networks to be massively more reliable than they are currently. It's all well and good if you live somewhere where you have a rock-solid connection, but most of the world doesn't. And is unlikely to anytime soon.

[mypalmike]

Some very popular CAD software already works this way (Autodesk Fusion 360 and OnShape, possibly others). The people with money to spend on such things tend to have good network connectivity.

[pjerem]

Alas, we are already in this situation. Remember that mostly every SaaS app is already a web app.