Well, then you have never heard of ksqlDB. It adds SQL and DB features to Kafka. It is backed by Confluent (LinkedIn) same company that developed Kafka initially.
We’re very aware of ksqlDB. I would recommend this video from last week where Matthias talks about some of the strengths and weaknesses of ksql: https://youtu.be/KUQuegJ4do8
My understanding is that ksqlDB is a read-only interface on top of streams and only helps people write better consumers. The problems mentioned in the blog post relate to producers.