30 minutes ago, this feature request was tagged status-completed:
I would like to raise the bar for late answers to enter the Late Answers Review Queue to 50 rep, which is the threshold after which users gain the ability to comment. Here are some answers that were posted by users with between 10 to 50 rep (yes, there's a little selection bias to be sure. I suspect most/all of these will be 10k links only by the time you're reading this. Note, all of these are from the last 5 hours.
Quoting the proposal by SE employee Jon Ericson:
Raising the bar to 100 would require changing two variables at once. Since that would make it harder to evaluate each individual change, I'd like to try raising the reputation for getting enqueued to the Late Answer reviews to 50 and reconsider upping it to 100 at some point in the future.
That seems to be it.
It's definitely a bug, though. From a comment:
Just to note, the answers should not be older than a month and the current spike should be temporary. – Jon Ericson♦