It was not expectation when they started, did a lot to lure many into the ecosystem. When you release it free, wait for the momentum to build, then you cut off, it is something else. And the worse is they did it in a very short time. Check out elasticsearch, the same route but did not abandon the 7 release like this.

I know all about ElasticSearch, MongoDB, Redis, etc. Yes, what they did sucks. No, it doesn't make the maintainers bad or anything. It's still on the user to know that anything can happen to that spiffy project they've been using for a while, and so be prepared to migrate at any time.