I was thinking the "30-60" day time window may be a somewhat subtle way of catching out engineers who haven't written a thing in that amount of time. that would be one way to identify low-performers. not unproblematic by a long shot, but quick, and probably somewhat effective. and it wouldn't require any deep knowledge of twitter's codebase on the part of the reviewers.
Printing it out as a mark of honor/shame is something a petty, arrogant tyrant would do. Musk has been around people who are afraid to say no to him for too long.