The temptation to blame victims is strong. I think it comes from wanting to reassure oneself that "it can't happen to me." So you have to actively silence that voice in your head, and assume that victims are actually victims unless there's real evidence to the contrary.
As advice for senior people, I'd suggest: don't apply for junior jobs. Apply to lead large teams, or start your own company. It can be more stressful than coding, but that's the way the industry is structured.
General experience doesn't mean much since there are few standards. Ones experience would generally be used to take more responsibility, do more important things or in other ways advance ones career. Not as some measurement of quality, since that would be very subjective.
In a changing industry it would even be expected that when things change a certain amount of people won't last, because they get squeezed out between new people coming up and old people already specialized.
So while surely part of the industry focuses to much on youth I think people jump the conclusion that it is widespread too quickly.
I don't at all find it hard to believe some interviewers would be biased against older candidates, especially for junior roles. However, given the person who posted seemed to have such a wealth of knowledge and experience, I was very surprised that they wouldn't have a very easy time finding a job even if places that refuse to hire older workers exist.