Many regular contributors to GNU projects didn't like RMS's involvement in the first place. He makes no technical contribtions, and he tends to post politically divisive flamebait-ey topics to the email lists. He'll also undercut his appointed maintainers by posting his own musings about decisions that have already been settled by the maintainers. More than once, he's used an effective "veto" power to force sub-optimal architectural choices in an effort to make sure GNU projects can't easily interoperate with non-GPL software. Refusing to expose gcc functionality through a library interface is the best-known example (which directly led many developers, researchers, and organizations to adopt clang and LLVM), but there are others, including a veto of Emacs features that would make it easier to talk to clang to power IDE-like features.

Most regular contributors found this behavior frustrating, and would discuss it privately, although rarely if ever discuss it on-list. These are people who are absolutely committed to free software, they were just sick of dealing with RMS. Wingo's stated attitude seems pretty typical: RMS was damage that needed to be routed around.

After developing this reputation, it's not shocking that most maintainers and contributors accepted his resignation from the FSF with a shrug. They were sick of dealing with him anyway - they're not going to protest to try to get him back.