I don't think there's some sort of "line" that Delve crossed and Corgi has not, more likely the financial upside for YC wrt Corgi is much, much bigger. They're not going to mess with that even if the screw over a few of their other startups. YC absolutely loves to tout this family dynamic across all their companies and alumni, but there is no way the relationship between a few dozen startups looks anything like that between literally thousands of companies. It's a scaled up tech-hype startup machine now, and has attracted the same MBA-types they supposedly defeated 20+ years ago.