The main difference is eventual vs strong consistency. Scylla scales great, but then the developer has to guard the consistencies. And that is quite challenging

The main difference is eventual vs strong consistency. Scylla scales great, but then the developer has to guard the consistencies. And that is quite challenging job, that usually trips even the most experienced developers. There is a middle ground, storage systems/databases that both scale and provide strong consistency. FoundationDB, Citus, etc. SQL databases are not only easier to query, but also enforce data consistency. While querying is their core job, it's hardly the only one.