The argument isn't that success is due entirely to luck. It's that you'll never know how much of that success is due to luck. It may be a lot or it may be a little.
Again, it seems there is this trend on HN to make it seem like anyone remotely successful got "lucky". Even worse is blurring the line between luck and hard-work so you can make it seem like their accomplishments aren't as important.
You can tabulate the odds of experiencing random radical growth 12 months in a row. It will happen to some portion of the population. If everybody is flipping coins, then 1 person out of 4000 will flip 12 heads in a row.
I am not arguing that most success is due to luck, or even half of it. I just think the statistical argument is interesting to explore.