I wonder if mid life crises possible arise in part due to the lack of a legacy we leave behind, whether it's kids, works for future generations, art, etc, and e

I wonder if mid life crises possible arise in part due to the lack of a legacy we leave behind, whether it's kids, works for future generations, art, etc, and even acts of altruism. Maybe doing selfless things can be just as strong a cure for the things you always wanted to do for yourself that you feel you haven't lived up to yet?