It would implement features specific to and invaluable for whatever I'm intending to work on, in such a way that I would feel like trying to do it any other way would be wasting my own time.
For an example, Clip Studio Paint - a tool unabashedly designed for and advertised to comic artists - has a design concept of a 'comic panel'. This lets you drag out a panel, instead of an arbitrary shape that you will use AS a panel. The panel, also an arbitrary shape, comes with functionality like "bleed" which allows you to continue drawing outside of the panel, but will truncate that content when you de-select the panel. It includes concepts like "path rendered borders" so that you can do weird stuff with borders that you wouldn't want to do with an arbitrary shape (like have characters break through them).
So, you end up with a nice little feature that can ABSOLUTELY be recreated in other programs. Nothing in that "panel" feature couldn't be done with a series of steps and possibly some macros in other applications. The problem is, it's all of that setup (wasting my time) instead of just having the feature available because it's a well-known process with well-known problems. These are the people who are best suited to know what good processes look like, and can build the best kinds of tools for those well-known processes. Of course, they have to keep up to date, but that's any software in any industry.
Just to head off any assumption that I prefer CSP or something, I will say that they fall woefully behind on other stuff that is not comic related (understandable because of their history, but still a hindrance to me using it). That aside, a separate example is that every single drawing program should have the ability for you to move "tool settings" onto another device. No question. I should be able to work from my tablet, and pick colors on my phone. Or work from my desktop and change brushes or sizes or store values from one project, while I open the next desktop tab for a different project, all on my second screen. As far as I know, none of them do this.
The overall point being "We've designed apps to work with data like a computer uses that data. I would like it if we started designing apps that work with data however they have to in order for humans to work with 'concepts' in whichever way they understand those concepts (to the best of their ability, which is pretty able these days)."