I don't think this will be true for average consumers. Perhaps for nerds like us, who enjoy a bit of tinkering and can put up with weird behaviors. I mean, are you envisioning that everyone would have their own custom messaging app, for example? Or email? Or banking app? I mean, I think most people's demands for those things are all extremely homogenous. I want messages to arrive, I want emails to get spam filtered a little but not too much, and I want my bank to only allow me to log in and see my balances, etc.

I could see maybe more customization of said software, but not totally fresh. I do agree that people will invent more one-off throwaway software, though.