It seems that a new addition was implemented by theymos, which is very useful for reporters: the age of a post.
As far as I see, this message
Old post: We generally do not moderate posts this old for on-topicness, substantiveness, multi-posting, and other "cleanliness" issues.
is displayed when attempting to report a post made more than 6 months ago.
When reporting posts made within past 6 months the message is not displayed.
Practically, this message is supposed to help both reporters and mods: reporters don't risk having their reports flagged as bad for reporting old posts (even though the respective posts needed to be reported) and mods don't have to moderate reports for posts older than 6 months, which reduces dramatically their workload.
For those unaware, those which used to report old posts risked to have their reports marked as bad. If I remember well, in 2021 or so, you could report posts from 2018 without risking having your reports flagged as bad, yet reporting posts from 2017 would lead to have your reports marked as bad.
So now this risk is mitigated. However, I believe that the 6 months is a very short life span for a post to be eligible to be reported. Maybe allowing reports from 2-3 years back would be more useful. For a long time now mods are not overwhelmed by the number of reports, therefore limiting the reports to only 6 months seems too short...
Nevertheless, the message is a great addition, especially for those aiming to reach / keep a high ratio of good reports. Thank you, theymos, for this implementation!
In the end, I have a small question about this part: We generally do not moderate posts this old for on-topicness -- shouldn't it be
off-topicness instead of "on-topicness"?