Hey SG10, CWG, and LWG,
I went through the past few years of straw polls and put together a suggestion of what feature-test macros are missing: I'm proposing that about two dozen need to be added. The draft can be found here: https://brevzin.github.io/sd6/papers/d1902r0.html
I included every paper on the straw polls pages, so if anybody has motivation for a macro for one of the papers I listed as "no macro necessary," please let me know. Also, if you disagree with any of my recommendations, also let me know. I already pruned an earlier list with some help, and I'd like to get this right.
I wanted to get this out earlier than the weekend before the deadline, but... that didn't happen.