Earlier quoted context omitted.
He wrote some code and gave it away freely, and all he wanted was a thank you. You say he should have hired a lawyer to write his own license. This is absurd.
If that's what he wanted what stopped him from adding one more paragraph to the licence saying something similar to: "The USER is required to publicly thank AUTHOR, and make the thanking reproducible in every copy of the derived work that uses this software." You don't need a lawyer for that. And if someone wants to use his work without attribution, they are free to negotiate a copy with different licence terms direc…
It is undoubtedly discourteous of AWS to release an OSS fork as a new feature without crediting the original author. It is not the end of the world. It is not a reason to go and change your licenses to make things more difficult for the other 95% of developers. But it is a reason to say "some people at AWS are just dang ol' jerks."