Amazon makes their game engine open source

I’ve read title and though that they maybe release source but with weird licence, but there it is this:

Amazon Lumberyard game engine as the Open 3D Engine (O3DE), under the permissive Apache 2.0 license

What are Amazon plaing? EEE? Starve competition and release something completely new?
Amazon is known for dirty practices and i just simply dont trust them.

I guess that there i chance that they just gave up idea because developing engine didn’t get them enough money.
Or just they made AWS bounded so hard into Lumberyard like it is with Android and Google so they hope to repeat that.