The notion that we're meant to take care of our parents in old age is cross-cultural. It conceptually makes sense to take on the mantle of care for your parents after they've cared for you your entire life, but individual relationships are far more nuanced than that.
Which is to say, not all parental relationships are healthy, and expecting a child who has experienced abuse (whether verbal or physical) to care for their parents is emotionally complex. Plus, not all people grow up to make enough money to support an elderly parent, just as some parents have enough money to live on their own well into old age.
Basically, the conversation around taking care of parents is complicated and multi-faceted, and the chips will fall differently for each family. That said, some people enter parenthood with the full expectation their grown children will care for them in the future, and it can cause rifts.