It's a very personal choice on how you allocate money. My grandfathers worked in a steel mill and a coal mine. They scrimped and saved for my parents and their siblings to have a better life. My parents were the first generation to go to college and became teachers. They scrimped and saved to give my generation a better life. I'm saving to give my kids a better life. If they needed it, I'd also step up and give money to my parents; fortunately, they don't need it.

If I were in your situation, I'd want to secure my own family's housing and retirement at least as much as your parents' housing and retirement, so as in many things, balance is going to be key. But if you truly value changing their lives at the expense/delay of your own, there's nothing stopping you from doing it and obviously nothing wrong with it. It's a very personal choice.