The use case that came first to my mind was the FAQ in a forum I use. It’s a topic kept without replies exactly for the purpose that it’s bumped when someone edits it.
This had numerous advantages for us.
First of all, many members noticed when the topic was being edited. I therefore never worried that a user with bad intentions could cause lasting disruption there. Even if someone reached TL1 and tried to add spam there, that would have been removed by the next person visiting the forum.
I was also able to add new information without having to find someone to review it first. I could trust that several community members would do this anyway when they saw the update. Probably faster than the person I would have asked for review would have seen it at all. In addition, I had not only one review from one user but from several. The responsibility was spread across many more people. Everyone helped improve the answer to the question.
I was also able to encourage new members to improve the wording. Users who are less technically savvy often find it difficult to understand overly technical explanations. It helps if, once they have understood it, they improve the wording so that the next person might understand it better. Of course, new users tend to have more difficulty with the correct formatting. But that wasn’t a problem because the community could correct it afterwards as soon as they noticed it.
The FAQs are pinned in the forum. I thought it was great that the date of the last edit was shown right next to it in the activity column. That way, the topic never looked outdated, but everyone could see that it was constantly being updated. Now the activity date won’t update anymore,
Within the past days I noticed wiki edits came to my mind first, because we had to find solutions for that before and I found all those topics from other users having the same problem. But actually the problem also exists for other meaningful edits where users add valuable information later. Of course those are not necessarily added to the last post. But I think that this is the most likely case. Discourse even forces users to edit their last post instead of replying several times in a row. I wonder how I’d feel on a forum I joined where the software tells me to edit my post instead of replying and if I did, no one noticed. It would feel like nobody cared. I guess it’s not a place where I wanted to stay.
In this forum meaningful edits for example happen when users are adding output from the serial monitor or pictures later.
Conversation example
new user: Hey I have problem X
member: Hey we can help you better after you shared images of X
new user: Can’t take images right now, will do that later when my child is in bed.
and then they put the pictures into that post later
I am worried we might miss these edits without the topic being bumped.
Getting back to your questions: while no one needs to know when a typo was fixed everyone might be interested in valuable updates. Visitors can easily tell that the wiki is actively maintained. Members can review changes on wikis and notice edits providing updated information.