Since luck can be defined as the crossroads of opportunity and preparedness, and since it takes work to be prepared for opportunity, and since it takes effort and a trained eye to spot opportunity...then ultimately it takes hard work to be successful.

Let's not let some billionaires who enjoyed friends with benefits skew the results of millions of successful people.

I should have worked harder to be sure I was not born to a single mother in poverty.

Yes. The definition of 'luck' stated in the article is just ... wrong. Luck as random, sure, but you become more 'lucky' by knowing more people but mostly being open to new opportunities, ideas, friendships. So yes, it is luck, but luck is (opportunity + preparedness + hard work + social skills) X iteration.