The original tweet (as I understood it) wasn't complaining about this in a legal sense. They know the license allows this. They were complaining from a place of

The original tweet (as I understood it) wasn't complaining about this in a legal sense. They know the license allows this. They were complaining from a place of asking for a little respect and acknowledgement. AWS has appeared to be doing a better job recently (from what I can see) in that regard. It's all around good PR. They lose nothing by thanking the maintainer/community for the work, even though the license doesn't require this. On the other-hand they build good-will. Given the AWS response linked above, it would appear AWS recognizes this, and so maybe they will better accredit the work.