You left this company in 2016, so by now, you know the outcome. You were there for under 2 years, so you only vested half. Based on my Googling, nothing physical was released and the company barely had a footprint. There's a patent (from when you would have been there), but neither you nor the "big rich man" are on it. It's also based in Oslo, which feels important to note.
I can't put my finger on it, but something feels very off here. I do agree the Reddit comments were quite inept, but at the same time, the conclusion doesn't resonate with me.
I think the real conclusion should be: A lot of startups are somewhere between risky and a straight-up scam, and very few are the next Google. If you're going to join a startup, YOU need to make sure it's the right one. If you don't have money, time is your most valuable asset, and you should be incredibly thoughtful about how you invest it.