Eh, I see how having an open mind could help with finding opportunities in life and make someone 'luckier' in a certain sense, but at the same time I also feel that there's still a huge portion of success that's down to things well outside of someone's control.
I mean, I often write about underrated creators on sites like YouTube, and while there's definitely some semblance of a correlation between marketing effort and success, it's very much a minor one overshadowed by a lot of other things. I know plenty of people who worked far harder than I ever could, and ended up struggling with only a few followers as well as people who seemingly just lucked into success purely from one random friend having existing popularity.
And I suspect it's similar outside of the internet too. There's a correlation between open mindedness and trying hard and promoting yourself and success, but it's not an absolute one and often overshadowed by a lot of other things.