There is also a reason why you don’t have general purpose applications. Most users understand that Excel is for data tables and Paint is for images even though some people have fun playing with the boundary and creating Excel paintings.
Interesting you bring up Excel. ChatGPT's chat interface is going to be Excel for the AI era. Everyone knows there's a better interface to be had, but it just works.
This is a reason why general purpose models shine. You don’t have to carefully characterize a task and put guard rails around it.