Ecclesiastics 9 vs 10

'' Whatever your hand finds to do, do it with your might; for there is no work or device or knowledge or wisdom in the grave where you are going.''

You have raised seriously important points here @humanearl. The sure is no better way to answer those who say your passion will not work or would not produce anything good is to actually give your passion your best. You have to work hard at it. It's a passion, but passion does not take away the place of hardwork.
Be committed to your career, to developing yourself creatively, professionally, and personally, and do something to move your career forward every single day. Eventually, this hard work will pay off and you will find yourself so immersed in fulfilling work that you love that your parents’ opinions won’t really matter anymore.

Also, guess who will likely be the first people to celebrate your big career successes? Your parents.