In theory… but capable and rational actors would know to hit certain growth metrics with a timeline for every stage of the company (ex. weekly KPI, deadline to find product market fit, etc)

The downside must be compared relative to the alternative, which is working at a job. Three years of “struggle porn” as you say vs three years at your regular big company job. In the former you learn an enormous amount, and can probably join the latter as a more capable employee anyway.