Ah yea the old “web scale” phase. I think everyone’s more or less accepted that very, very few startup-level (or even SMB-level) workloads need more scalability then Postgres/mysql gives.
My favorite example is that Twitter used mysql for all tweets, writing ~5k/s 24/7/365, until about 2016ish. Well into being a public company with billions in revenue and 300mm+ MAUs.
3/4 companies in the Bay Area senior software engineer interviews require a System Design interview where they will tell you "what if you had 10m users" and expect a distributed write-heavy sharding answer
You’re not wrong in the literal sense. But the “inside baseball” of that question is just that it’s a prompt to talk about how you would horizontally scale a system should the need arise. It’s not a prompt to start questioning whether 10mm or 200mm is the specific limit.
Lots of people were mad that my employer developed a new distributed NoSQL database engine, but it was literally just an API to encapsulate what an application doing "sharded MySQL" would do in its own data tier. A lot of this is a question of framing and storytelling.
Sharding, write scalability, and similar are the technical advantages that can matter at scale (and mattered a lot more before SSDs became so common), but I think for most users the only tangible ?benefit? was the schema less nature.
Wait, was that the reason people were doing NoSQL? JSON support? I thought it was about sharding, write scalability, etc.