I definitely agree that people are slow to switch from what they know, but I don't think it is impossible to build software that will make people jump ship on the old stuff.
Take Sketch for example (http://www.sketchapp.com). Everyone on our team used to use Adobe Illustrator, and now everyone uses Sketch instead, because for what we do, it is simpler and better.
Good example, I think it is easier to dislodge old tractors with tools built for one specific thing, i.e. that do less, but do it so much simpler that they're just a joy to use (at least in comparison).
I've often though a good strategy would be to look at some incumbent (Quickbooks, Photshop, etc) then choose a subset of their customers (Landlords, Real estate agents, etc) you can target more effectively than they can.
Do you think that in this particular case (Illustrator vs Sketch), the fact that Adobe employed a subscription model sped up the process of people being a bit uncomfortable and looking for alternative solutions?
