"I suspect that many posters have had their posting rights suspended because of approving comments the system deemed uncivil, and are no longer taking any risk of getting banned completely - so the red button it is.

I have also had innocuous comments deleted for being uncivil like the following:
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"Yeah. an hour and a half is not enough time to avoid anxiety if you are travelling with small kids, especially if you have not done all you could in advance via online check-in."
Delete
This comment was rated below the civility threshold for publication.
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Although this is not a good example of an insightful contributing response to an important issue - many of those comments are being deleted. Eventually posters will just give it a miss instead of wasting 20 minutes posting intelligent commentary, and we will end up with Facebook comments of one second "what he said" responses."

Note - this post was also just deemed uncivil and deleted.  Another victim of the red button brigade.