The 10-year database architecture cycle:
2015: SQL is obsolete. Schemas are too rigid. Put everything in NoSQL JSON documents.
2018: Wait, we need to join users and orders. Let's write a 400-line nested loop in JavaScript to join them in RAM.
2021: Wait, if the server crashes halfway through the loop, we lose money. We need ACID transactions.
2026: Quietly puts everything back in PostgreSQL and never speaks of it again.