I can't imagine a project so wildly successful and stable that the session URL in a commit history is relevant after 5 years, let alone 30. Git is only 21 years old. I'm not deciding team policies with a multi-decade view.

That said, I wouldn't agree with using the session URL as the entire commit message, or even with letting the session URL make up for other missing details. But to me it's an at-worst neutral change to add it to an otherwise acceptable commit message.

While working on Firefox, I do sometimes look back at Bugzilla (the project's issue tracker) activity from 26 years ago to try to figure out why some code is the way it is. However it feels hard to believe that the role of LLMs in another 20 years will be close enough to the way it is now for a session history like this to be very useful.

30 years ago is only 1996. I very much do debug code from that time and am glad for anything useful written in the commit message. URLs are useful, because either the website still exists or it is maybe in the wayback machine.

That's fair :) Can't say I've looked at any 30 year old commits lately myself.