According to research (see "The Millionaire Next Door"), about 20% of millionaires were born into wealth. That means that when you meet a millionaire, s/he's four times more likely first-generation wealthy than having inherited wealth.

Still, with 10% of Americans being millionaires (https://www.statista.com/topics/3467/millionaires-in-the-united-states/), this means that on average, coming from a wealthy family improves your likelihood of being wealthy more than two-fold.

This is a clear demonstration that becoming wealthy isn't just about hard work, smart decision-making, resilience, and sacrifice. There's usually a lot of luck involved too.

That luck could be genetics that make you more attractive (which research shows leads to better outcomes), have better hand-eye coordination and/or speed (so you can become a professional athlete), intelligent, etc.

It could be being born to a family that values education, and pushes you to excel.

It could be meeting in school the right people who later open doors for your career.

So, no, it's almost never "just luck." But it's also almost never "she did it all on her own with zero luck involved."