[rbehrends]

With respect to publishing, it depends on what conferences you target with your publication. For example, at the intersection of the software engineering and PLDI communities, you'll have quite a few researchers interested in proper tooling. ASE (Automated Software Engineering), for example, is a highly regarded conference that is really interested in this type of research.

There are also other incentives for researchers to create usable tools and implementations (assuming that the tools are actually meant to be more than experimental prototypes).

To begin with, compiler developers traditionally "dogfood" their compilers. They may still be willing to live with things that you wouldn't have in a commercial product, but they can't and don't completely neglect usability, either.

Second, usable tools are more likely to be adopted by other researchers, creating a positive feedback loop with respect to future publishing opportunities.