That would probably end up in a messy thread but I hope it doesn't. Each fight means a discussion about the skills of each boxer, their statistics and experience, odds, etc. If 5 matches are discussed in a single thread, that thread will not only become disorganized but grow into one spammy megathread.
I think we should do it the way we've done it before instead of making it such that some people won't be notified of the new match and ask to not effectively discuss the upcoming match when compared to each having their own thread.
Maybe for me and for some, I'd like a specific discussion about a particular boxing match so we can think about the strengths and weaknesses of each fighter and provide hints or tips for those who like to bet. certain fights, the flow of discussion will always be themed about one particular match.
If there is someone who are going to open a specific thread for a specific fight then we can discussed everything under the sun there.
But if there is no specific thread maybe the fight is not that huge for boxing fans, then it falls on this thread simply as that. If could be disorganized as you have described it, but there are boxing fans that knows when to discussed that fight that is buried on this thread or just continue with the latest fight not having a specific thread.
So I disagree with your thoughts, and if you have look at this thread and back read, your point has been discussed as well. So we don't need to discussed it again, just saying. If you want specific fights to discussed then you can open a thread about it, simply as that.