Or they could, you know, just respect the new license and publish their changes and part of their "secret sauce". I bet it would be anyway tightly coupled to other AWS internal services so nobody would get hurt in the process.
Edit: fixed typo
Edit: fixed typo
The license is plain vague.
And it's ES that's forcing AWS to do this.
Anyway I agree that the license is too generic and can use some more details but IMO it should basically cover all the automatism you explicitly create to manage the software you are selling access to. I mean, there is no need to publish the secret sauce for EC2 because it exists anyway and it's publicly available anyway.
To sum it up, I'm not against the spirit of the license but I agree the implementation should be better.