[stavros]

I feel like the phrase "all you need is Postgres" has the (often unspoken) continuation of "until you actually get to a trillion messages".

In other words, the developers you're envious of didn't start with Cassandra and ScyllaDB, they started with the problem of too many messages. That's not an architectural choice, that's product success.

[dondraper36]

Absolutely. To put it differently, unfortunately not everyone has a chance to be part of a product's organic evolution from "all we need is Postgres" to "holy crap, we're a success, what is Cassandra by the way?"

[SatvikBeri]

As a data point, I've been at two data-intensive startups where they eventually needed to pull (some) of their table-like data out of postgres, and for both that was past a $100MM valuation.

This varies by domain of course, but non-postgres solutions are generally built for very specific problems – they're worse than postgres at everything except one or two cases.