I want to measure the inflation of "favourite" flags in chat rooms, but can't find any way to query it.
All Q&A sites exist in SEDE, but why not chat.stackexchange.com?
I guess the argument can be made that chat transcripts shouldn't be made public through the data explorer. Different from the Q&A data, that's not really in the "public interest".
Chats are informal conversations between people and have little value for future generations. The way I see it, chat is explicitly outside Stack Overflow's mission of creating an archive of canonical content.
That said, it's of course perfectly legal for anyone to use and analyze chat content - like everything else on the network, it's published under the Creative Commons Wiki license. Perhaps there should be a chat stats dump?