What benefit is there for closing all topics? Why is there a problem to people, when facing the same issues as the OP, to add a reply to an already existing topic, even if said topic is old?
Discourse makes is so seamless to break off-topic replies into a new topic with so few clicks, and thanks to AI Helper you don’t even have analysis paralysis deciding title, category and tags, that in my opinion a strict rule on closing all support topics feels outdated and something that would be necessary on old forum software.