Founder mode existed, it just didn't have a catchy name. And I absolutely believe that it was the right choice for your team, exactly for "founder mode" reasons.

In other words, I don't think that the social or technological reasons in the document were that strong, and that's fine. Rather, my external armchair impression is simply that OS and hypervisor were not something where you were willing to spend precious "risk points", and that's the right thing to do given that you had a lot more places that were an absolute jump in the dark.