Sorry for the meta-question, but I saw a thread below that was locked where the moderator had redirected the discussion to an older post-- but when I went to the older post (early April of this year) and tried to comment, I was told that the post was too old to comment on, even though 2.5 months really isn't that long ago. Is this something new or just something that's been around a while that I never noticed until now?

It's been around a while. It was introduced as the forum was getting silly people replying to 3 year old posts and producers continually bumping posts for more exposure.

I have unlocked the post due to new information. I renamed the thread simply as "rich" (in case he wishes his username not to show up publically).