Yes, the license allows it. So, technically they can. But you have to admit that it's a bit of a dick move.

The reality is, ElasticSearch with all of it's capabilities would not exist if the company would not exist.

How many other new interesting products will no longer be built as open source, because they know that AWS can just co-opt them and then their business will be effectively over.

The laws and licences cannot possibly cover all the details of the real world, there needs to be some humanity involved, some "let's try to not be assholes" attitude.

I prefer to live in a world where I'm not required to be a robot. Following all the clauses and laws to all the details will end up with that. It's not a great path.

We all need more empathy.