Yes, I expect it was an honest mistake from the first person to reply,
and then everyone else was just replying to each other. I didn't
realise I was sending emails to internal-l, I thought we were on
Wikimania-l (that's the tag in the subject line).

I was the first person to reply, and it was not a mistake. I replied to the original announcement on Internal-l because I didn't want to start a publicly-archived thread second guessing them and criticizing them. People tend to take negative feedback better when not performed in a public forum where everyone and their mother will pile on. It gave Nicholas the chance to reply before sending a public announcement, and he did so quite professionally. I don't personally consider the matter one that requires a big public debate.