This is more trouble than it's worth for the mathematicians of today. What exactly is gained from these ORCIDs? A DOI auto-generates a clickable link, allows for automatic reference tracking, and (hardly an intended feature but perhaps the best one) helps readers find a copy in places like sci-hub and LibGen (on sci-hub, DOI is the only lookup option that currently works). With an ORCID, I could make it double-clear that the D. E. Knuth I'm citing is the real Donald Ervin Knuth. Nice, but I'm supposed to learn a new command and spend 10 minutes researching authors per paper for that?