Because SQL and relational data. They're (MySQL and Pg) a lot more familiar to setup and maintain. There's a lot of managed services offering for the usual SQL databases.
Cassandra/Scylla come with a lot of limitations when compared to typical SQL DB. They were developed for specific use cases and aren't at all comparable to SQL DBs. Both are completely different beast compared to standard SQL DBs.
Cassandra/Scylla come with a lot of limitations when compared to typical SQL DB. They were developed for specific use cases and aren't at all comparable to SQL DBs. Both are completely different beast compared to standard SQL DBs.