Neither of these issues have anything to do with the license.
Either Elastic's code used by Amazon is indeed stolen proprietary code and no licensing change is needed to obtain reparation, or Amazon is making lawful use of FOSS source code and the question boils down to "if I publish code under a FOSS license, can anybody use it?", to which the answer is obviously yes. And if you'd prefer it to be "no" then don't publish FOSS.
Regarding the trademark, this indeed seems (to my non-lawyer eyes) to be an infringement (or extremely borderline at the very least) but isn't related to licensing.
The trademark has to do with licensing insofar as if a major reseller of your OSS licensed product will infringe on your trademark, the easiest solution might be to modify the license. Especially when the alternative is lengthy trademark disputes with a huge company with a lot of lawyers.
At the end of the day offering an OSS license becomes less viable when it seems like major players aren’t playing fairly.
Typically the standard for trademark cases is whether or not customers will confuse the two competing names/products/brands.
It's quite possible that because both companies target developers, architects, etc who're more than able to distinguish between the two companies' offerings... that Elastic's lawsuits didn't go anywhere
Sophisticated Users are definitely one factor that weight in favor of developers, but in my view it’s outweighed by the degree of similarity of the two marks, the similarity of the services, the uniqueness of Elastic as a mark, evidence of actual confusion (before reading Elastic’s complaint, I was confused by the names, and I’ve been involved in making decisions about the use of these kinds of services.)
Trademark law goes by category. Elastic uses theirs for a software product as well as a service, whereas Amazon is using it for their cloud services (not as a standalone software product). This is why Apple Corps (music, Beatles) and Apple Computer Inc. were allowed to coexist.
This situation is a very fine line between the technicalities that the trademark law was written for. Amazon knows this, and they have the money to set legal precedent in court to have it their way. And so stomping on Elastic's trademark is the route they chose to further benefit from that company's reputation.
Either Elastic's code used by Amazon is indeed stolen proprietary code and no licensing change is needed to obtain reparation, or Amazon is making lawful use of FOSS source code and the question boils down to "if I publish code under a FOSS license, can anybody use it?", to which the answer is obviously yes. And if you'd prefer it to be "no" then don't publish FOSS.
Regarding the trademark, this indeed seems (to my non-lawyer eyes) to be an infringement (or extremely borderline at the very least) but isn't related to licensing.