The problem with these discussions is that you can always get a lot out of any given architecture, structure, db approach or whatnot. Can. There's just a lot of daylight between "can" and "likely will."

Ultimately, everything has its limitations and tradeoffs. If we respect them, it's generally a smooth ride. Problem is that we rarely do... within a company (startup or otherwise) under real conditions. There's also a dynamic where we build until the point where something stops us. Tech debt, complexity, over-engineering, under-engineering, feature bloat or antagonism between early decisions and current goals.

There's a self-regulating aspect to this. If architecture is spot on, perfect for the task at hand we can move faster to reach the point where it no longer is.