This is why there's an endless cycle of shitty SaaS with slow APIs and high downtime. People keep thinking that scale is something you can just add later.
Let's say you're a team of 1-3 technical people building something as an MVP, but don't necessarily want to throw everything away and rewrite or re-architect if it gets traction.
What are your day 1 decisions that let you scale later without over-engineering early?
I'm not disagreeing with you btw. I genuinely don't know a "right" answer here.