I'm a grey beard who applied to a company specifically advertising for young developers. Got the job without mentioning my vintage. That was six years ago and they still haven't seen my face. I waited a while to gently break the news to them. If you're a technological senior citizen remote work is your friend.
How did they "specifically advertise for young developers" without running afoul of age discrimination laws?
In this case, someone would have to sue them. For instance, an older developer who interviews, believes he or she is being discriminated against on the basis of age, and uses the advertisement as further evidence in the complaint.