By us, of course! I'm sorry, because I'm going to introduce a little bit of FUD, but I think it's a healthy dose:
The problem is not that we are not well served by what we currently have. The problem is that most computer users out there are not. And as a consequence those people select other operating systems. Why should we care? Because marginal platforms can only survive thus far. Yes, there are still people writing code for the C64 and the Amiga, but they are few and mostly irrelevant, except for themselves. Do you want to see Linux there? I certainly don't.
So, It's OUR need to appeal to as many users as we can, and serve them well in as many use cases as we can, to ensure our own survival. Specialization and immobilism will be death for the platform.