Rephrased: Amazon played hardball with open source Elasticsearch, limiting elastic's ability to make money and forcing a license change. Now you should use Amazon's fork instead! This is not a good outcome for people who want an independent OSS ecosystem.
I tend to think that it, more or less, is. Elasticsearch (as an open source product) is not independent. Its reliant on Elastic co, who have a demonstrated history of reducing its FOSS-stance in favor of making more money. Of course, they had to do this; Amazon forced them into a corner, similar to MongoDB. But the fact that there is a critical company behind these two databases, who can be strong-armed, is a threat…
Postgres had a huge head start here, and was built in a different world WITHOUT an Amazon equivalent.
Are there a lot of major contributions to (not just on top of) ODfES outside of Amazon? If not, I'd be fairly worried about using it in a non-AWS-provided way in the long term, now.