I think we should come up with a set of written rules how moderation is expected to work.
Please note that we used to use mailing lists for a very long while and Discourse was/is meant to replace those mailing lists with a mechanism which allows for better handling of splitting off topics into new threads and occasional CoC issues, but not really to limit expression.
Things like long running threads, repeated discussions and sometimes heated discussions were normal on mailing lists and are very much part of the Python culture we have. If people enjoy the discussion, they should be able to do so, without moderation kicking in.
For mailing lists, it was easy to mute a thread. Discourse makes this even easier. There’s no need to shut down threads. People can just walk away – very much like they do in real life at conferences and similar events.
Regarding editing titles, I think the best approach is to suggest this as part of the topic discussion. Moderators may help with the editing in case the OP doesn’t have permission to do this, of course.