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SQL databases don't support easy schema evolution, sharding and so on.

PostgreSQL directly supports table sharding. https://pgdash.io/blog/postgres-11-sharding.html

Schema evolution is supported by pretty much every ORM you'd care to use; it's not the job of the SQL database to handle the migration. I'm using Prisma and you literally change the software spec for the schema and say "migrate", and it creates the migration SQL and applies it to the Postgres DB programmatically. That gets you deterministic schema evolution and not the "my schema isn't actually reliable" that NoSQL/no-schema databases rely on.

And then you have CockroachDB/YugabyteDB that give you extreme horizontal scalability, with full PostgreSQL compatibility...

And bang, the last reason to use MongoDB vanishes.

I think a missing piece is making materialized views fast since there will always be cases where someone wants to denormalize to get around performance issues, even with well designed indexes.

And Mongo is even worse. You can easily change document structures, but now you have inconsistent data over time.

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