Best case, good people leave and the company spends more than it needed to on onboarding new people.

Worst case, good people leave and your team never fully recovers, the product is technical garbage and you end up spending on a rebuild, or the product fails. Considering the product is the foundation of the project, ignoring warnings from the people building it would be like ignoring someone yelling "Fire" inside a wood mill. They know the product, wood, doesn't come out very well given the current circumstance, fire. We should probably listen.

Ultimately, more money and happier people could have been had if things were done pragmatically but correctly. There is of course such a thing as an overengineered product, so there is certainly a balance between pragmatism, speed and quality. But the mindset being brought up here is that you can forsake quality and happiness for more profit without consequence, and I suspect that's not truly the case.

In every case the companies they were trying to build up failed. Being vested owners, they lost money, and time.

I agree that makes sense, but the statement was "technical people are the ones to suffer for it". If that was true, it'd be as intended