Back when I first started taking client work, I had plenty of trouble securing contracts because owners/execs saw a kid at the table, not someone who was going to solve their problems for a respectable amount of money. This was always the result of prospective clients insisting to have a video call/meet prior to any work being done.
Quickly after, I strongly refused any situation that would give away my age. I'd be lying to say I didn't receive a lot of opposition but when your chance of securing a deal is sub 10% and tons more time wasted, it's easy to just drop the prospect.
By now, my age is (for the most part), no longer a deal-killer, but I still usually do the same thing unless they're referred by an existing client. It's a huge timesaver.
I was actually pretty lucky to be able to work with the places that I have, but it was a lot of applying everywhere and hoping they didn't ask how old I was on the phone interview.
I actually had to grow a beard before people stopped asking me how old I was and focused on asking me technical questions :D
it does seem to be taking a turn, I have seen a lot of kids hanging out at the local tinker mill working on cool projects and talking about starting their own companies. which seems like a much more accessible thing than it was when I was a kid.
I think this is an important statement. Kids tinkering in their basement have knowledge to do great work, but are often overlooked because of their age or education.