Switch back gcc to simple C dialect? Make gcc generates pthread TLS for __thread keywords instead of using ELF TLS symbol support? libdl-ized libstdc++?
Make the glibc compile with simple C compilers? Make it completely libdl friendly?
Remove bash-isms from bash?
Calm down on GNU symbol versioning?
Deprecate _Generic from ISO C. Restore constant-expressions only in ISO switch/case and ISO initializers?
Acknowledge the toxicity of c++ syntax grotesque complexity?
Acknowledge that open source is not enough anymore: we need open software which is lean (runtime and SDK) and stable in time?
All but like two of those are important at all for advancing the FSF's missions. They would also completely break backwards compatibility. Half of those aren't even under the control of the FSF.
apart from that, the tendency is to less posix and more friendly and consistent shell syntax.
zsh is even worse then bash when it comes to zsh'isms and then there are fish, elvish and several more which actually break sh compatibility, and that's a good thing. there is plenty of room to modernize
Make the glibc compile with simple C compilers? Make it completely libdl friendly?
Remove bash-isms from bash?
Calm down on GNU symbol versioning?
Deprecate _Generic from ISO C. Restore constant-expressions only in ISO switch/case and ISO initializers?
Acknowledge the toxicity of c++ syntax grotesque complexity?
Acknowledge that open source is not enough anymore: we need open software which is lean (runtime and SDK) and stable in time?
restore the noscript/basic (x)html web?
etc...