AFAIK people didn't take MongoDB seriously from the start, especially with the "web scale database" joke circulating. The Neo4j Community version has been under GPLv3 for quite some time, while the Enterprise version has always been somewhat closed, regardless of whether the source code was available on GitHub (the mentioned license change affected the Enterprise version).
Regarding CockroachDB, I must admit that I've only heard about it on HN and don't know anyone who seriously uses it. As for Kafka, there are two versions: Apache Kafka, the open-source version that almost everyone uses (under the Apache license), and Confluent Kafka, which is Apache Kafka enhanced with many additional features from Confluent, and the license change affected Confluent Kafka. In short, maybe the majority simply didn't care about these projects very much, so there is no major fork.
> It cannot be because the Redis and Elasticsearch install base is so much larger than these other systems, and therefore, there were more people upset by the change since the number of MongoDB and Kafka installations was equally as large when they switched their licenses.
I can’t speak for MongoDB, but the Confluent Kafka install base is significantly smaller than that of Apache Kafka, Redis and ES.
> Dana, Bohan, and I worked on this research project and startup for almost a decade. And now it is dead. I am disappointed at how a particular company treated us at the end, so they are forever banned from recruiting CMU-DB students. They know who they are and what they did.
Call me a skeptic, but I can't see this as a fair approach. If your company fails for whatever reasons, you should not recruit the university department/group/students against your peers (I can't find that CMU-DB was one of the founders of Ottertune).
Wrt Andy, here are [1] somehow interesting views from (presumably) previous employees.
[1] https://www.reddit.com/r/Database/comments/1dgaazw/comment/l...