When I first entered the workplace as a programmer, I was not taken as seriously as I might have been because I was so young. I got my first programming job at 16, and even when I started doing major consulting gigs across the country at 19, I looked really young for my age. One client remarked, upon meeting me, "You don't look old enough to operate a car, much less our computer." It was always a challenge for me to get people to evaluate my ideas based on their merit rather than their source, and to evaluate me based on my work product, rather than where they were at in their career when they were my age.
I have worked for myself for many years now, but if I sought employment elsewhere, I'd probably face some difficulties because I'm much older than the average developer, and people would assume that I'm stuck in old technologies as many professional developers my age are.
But the truth is that unfounded discrimination happens all the time in the workplace, for all kinds of reasons. Almost nowhere is a true meritocracy. At one place I worked, even when I was at the perfect average age for software developers, and white, and male, even then I was cut out of the circle of the key developers. It was because the developers, owner, and key management liked to stop working many days around 10:30am and start drinking heavily, maybe stopping back by the office briefly some time in the afternoon, then go back to drinking steadily the rest of the day until 6 or 7 pm. I didn't really do that with the same kind of endless enthusiasm that they did. I didn't fit in very well.
If you find a group of people that accept you the way you are, and evaluate you based on the work you do, you've found gold. If mere excellence is the currency of the realm, and all they want from you is to be the best you can be, then that's a glorious place to be. But finding such a place is very rare. It's hard to find that in a workplace, a church, a group of friends, or anywhere. And if you're struggling to find that, it's not entirely because of race, gender, age, or sexual orientation-- it's mostly because of people's basic nature.