You’re getting some great advice here.
My business partners were early 20’s when we started Rocketspark and age didn’t seem to be a factor. Our customers are mainly businesses and most were older. A great product and service were the key for good word of mouth to kick start the growth.
Having your customers tell your story with great testimonials / reviews helps bypass potential age bias and having a hot looking website with the testimonials woven through is a great way to get the message across without having to say it yourself. Be sure to ask clients for reviews and testimonials as they are not often given out without asking even when you have very happy clients.
Hope that helps.