I’ve noticed that Discourse can somehow track topic renames, but it’s good to know that it works like this (even this works: https://discourse.slicer.org/t/3111).
It’s good to know this works. I will note that for people using the email interface to discourse renaming the topic changes the subject line, and this disrupts the message threading, and this can make it hard to follow discussions. So changing topic names should be done when needed, but not routinely.