I agree, but the actual words used when this discussion comes up very often are much closer to "What idiot designed this shit?" rather than "My coworkers made architectural choices based on facts that are no longer true". (At Google the latter was perhaps more common, but I've heard the former in startups a lot more frequently, and certainly on Internet message boards.) I'm perspective-taking on the part of all sides; I hope that it's apparent from each side being called an idiot in turn and the company succeeding in the end that I don't actually believe any of the participants are idiots.

Once the next round of developers join, the scrappy MVP has usually been pushed far enough to be messy and maintainability becomes an issue. Seeing that might trigger the "idiot" reaction, The old guard appreciate how far it's come.

I believe they used the right word. Not because those that did make the decisions were, in fact, idiots, far from it. It's because many times, that's the attitude of people who decide that things have to change.

"based on facts that are no longer true" I don't think each successive wave is necessarily thinking about facts that were true but are no longer true. I think being opinionated about the tech stack you have to work with is often not all that rational. Trying to substitute concrete rational behaviour on the desires of new waves of employees might seem nice, or at least politically correct — but there is often no specific technical translation for "what idiot wrote this"; it's a cultural thing.

Wrong: "made architectural choices based on facts that are no longer true"

Less wrong: "made architectural choices based on personal preferance"

Don't be such a politically correct idiot!