I am totally sympathetic to the "this isn't a legible link for machines". After all, this utm_source implies that some human is looking at the logs manually (or at least, trying to decipher aggregated utm sources manually). However, we are well into a transition to a world where this isn't true, and 'utm_source=Robin_Sloan_sent_me' is probably just as good as 'utm_source=robinsloan.com' for LLMs of 2026+.