Why are there no DOIs for NeurIPS papers?
I work at Crossref (there are other DOI agencies too) and it looks like the proceedings used to be published by MIT Press and registered with Crossref as book chapters - see search results. But there isn't anything with us since 2007 so not sure whether the conference moved to a new publisher that isn't a Crossref member or something like that? I searched the ISBN database too but that doesn't help much. Probably best to ask the conference/organisation directly? Let me know if you find out!