Comment by antirez

The SSPL is useful exactly for the reasons you outlined, mainly. To preserve the ability to make money of the original authors is just a side effect. The SSPL point from the point of view of the Free Software Movement is (whatever was the reason for the creation of such license): people will start to write less and less free software (it is happening already) if they see their software exploited by megacorps. As less free system software is produced, the society captures less and less value. It's exactly the same idea as AGPL. Also if the original authors have a viable income, they no longer need to do things as a side project, and can write more and better free software, so also to avoid Amazon stealing the potential money output is a direct way to maximize the free software main goal.