Working hard works better if you are lucky in the first place. You need to work much harder than the lucky ones to leverage opportunities if you were born in a third world country, or when you are physically disabled, or simply if your parents aren't wealthy.
I can assure that your experience isn't representative; probably not in "big" enough spaces. It's deeply ironic, but the bigger you go, the more you can easily see luck as a factor (e.g. daddy's money)
The hard work I'm referring to is all the effort to get to place where you have even be "lucky" or serendipitous.
For example, professional networking is a tremendous amount of work. But in meeting, bonding and potentially working with those people opens so many possibilities for serendipity / luck what have you. Sure there are those with Daddy's money, but more importantly the relationships, networks and resources that Daddy has are more important than just the cash.
Nepotism, sure, but that's how the society has pretty much always worked.
The world is full of people that worked really, really hard on something and failed to achieve the specific goal they set out for.
Success is complicated.