On the contrary, this is win-win for everyone: Amazon now has to make their fork competitive with Elastic's, so they'll have to invest more resources in open source development. Elastic is also still free to grab their Apache-licensed improvements.
Meanwhile, if Elastic's future improvements are better than AWS', it'll drive use of their services over Amazon's.
Elastic doesn't need to make more money than Amazon. They just need to be able to make enough to have a healthy business, and so far they've achieved that. $500MM yearly revenue with 40+% growth is nothing to scoff at.
It really seems like Elastic's motivation here is jealousy more than anything else. Which I understand from an emotional perspective, but from a logical perspective it's a big business blunder they've made IMO.
I totally agree, I think this is great for the community because the writing was on the wall ever since the initial X-pack source-available drama as well as the original OpenDistro drama.
Meanwhile, if Elastic's future improvements are better than AWS', it'll drive use of their services over Amazon's.