It's very easy to say even when you're poor.
I grew up relatively poor. I spent numerous years of my adult life poor.
It was easy to say regardless of how much money I had.
In fact, I hate the opposite premise: everything that happens to me is out of my control, my choices are out of my control, my mindset is out of my control. I'd rather own 100% of the blame for my circumstances than wallow in victimhood forever. Wallowing gets you nowhere, it won't actually get you out of the situation; taking responsibility in one way or another (either for your present mindset, or for choices you made that got you there), is the required minimum to get out.
This is a choice you get to make. How much willpower do you possess? How much discipline do you possess? What are you willing to do about your circumstances? More money doesn't dictate willpower or discipline, if anything it makes you soft, gelatinous.