What's needed is more jobs that pay people to write open-source -- for example, but contributing libraries back to the community, or at least bugfixes.
Yes, definitely. My personal experience is that it's not always missing appreciation but more practical issues that keep companies from contributing more (money/time/developers).
My clients usually understand the benefits of using free software and express an intention to contribute back, but the process of contributing is not well understood.
If you take some piece of open software and customize the hell out of it for a few months, you can't just expect the upstream project to gratefully merge all your stuff because it's "free features". So it takes time and energy to work with the upstream project to identify useful parts and carefully integrate them into the upstream project, all while the customer is already in "works for me" mode and doesn't care to change already deployed software....
This is absolutely true. People worry about building on top of platforms, but when it's an open source platform, they don't seem to perceive it as having the same risk.