Earlier quoted context omitted.
I would say "partly" rather than "largely". I think the reason luck seems to be such a significant factor is that everything else that depends on your idea, execution, networking, and so on are all tough, and exceptionally so en masse. So, to minimise the impact of luck, you'd need to hit home runs in every other aspect which is unlikely. If your idea is great, but the rest so-so, then luck might seem like a stronger…
I beg to differ. Take the best 10 people, which are all the most dedicated, hardest working, most compentent: If these compete on the same idea in the same field, only one of them can succeed. After all, running a startup means taking risks, and risks are just another word for stuff that you don't have under control, and which is best described by probability.
More realistic would be 10 ventures where a couple bail, another couple just don't have a professional network, another has a great network but an ugly design or awkward name, and so on.