Most of these threads are pretty well updated.
So, there's really no reason why any of you should have to go through the entire thread to search for anything.
Personally, I don't even go through the threads for news. I go to see what you guys are talking about, cause, yes, my life is sad, I think you guys are interesting. I don't even search the thread for that. I go straight to the last page
Locking the threads would be a horrible disaster. More than one person contributes and posts new things. It's not up to the moderators to do those things. News here is posted by the community, and you can't ban most of everyone from posting while exempting a few others just because you feel there's too much chatter about things you don't want to read about.