This happens to us regularly too, where multiple people will be working on a response and we don’t realize it. Then we hit the reply button about the same time or one person spends a lot of time writing a post and then just before they hit reply, they see a new post come in that negates the sometimes lengthy post they’ve been working on themselves.
This would certainly be a cool feature to help with these situations. You could then babble or slack the person to see if your replies are similar and only one of you needs to write the post.