That's exceptionally untrue - though it can be true in context. In the city beside mine, renting a place downtown, and working in the grocery store it's very possible to save $500 per month. For reference, minimum wage is the equivalent of $1700 USD, and renting a one-bedroom, all in will cost roughly $454 USD. With cellphone (250GB of 5G speeds) costing the equivalent of $15 USD, and groceries and electricity costing another $350, there's still plenty of space. Investing that money in the S&P at its historical rate, for 45 years will yield $2.3 million (rounded down).
Now, quality of life would be rubbish. But it's technically possible.
Now, quality of life would be rubbish. But it's technically possible.