I saw much of Duval's 59 on TV, and saw very little luck involved in it. It was probably the single most impressive display over 18 holes I've ever seen (he hardly had a putt longer than 10 feet), and in some ways a more impressive round of pure ball-striking than anything Tiger has done.
I didn't see Larsen's perfect game, but he was a pretty mediocre pitcher over the course of his career. The one perfect game I did see -- Len Barker for the Indians back in the 1970s at a truly dumpy stadium -- also came from a pitcher with a pretty mediocre career. But Barker was very good that night, perfect in fact, and benefitted from very few if any outstanding defensive plays that saved his game.
In that respect, I think Larsen and Barker were both "luckier" than Duval, whose 59 was perhaps the pinnacle of someone who was playing the game at an extraordinary high level -- the only golfer, in my view, who in the past 10 years or so who played the game anywhere near Tiger's level, from the standpoint of pure shotmaking (admittedly, a faulty putter at some key times probably cost him a major or two.) Duval shows some signs of coming out of his slump; golf needs someone like him to step up to Tiger.