I suspect you would find an age bias in most industries with a learning curve for lower level positions, i.e the type where you apply mainly by sending a cold resume. Try getting started as say a chef or electrician post about 30.
Attempting to immunize yourself from claims of bigotry by handwaving about virtues that offset the stereotype you're defending is the second oldest rhetorical tactic in the prejudiced debater's handbook.
The first of them would be, "but some of my best friends are older adults!"
This was a shitty way to argue; my comment above was directed at a comment on the thread, but this one feels more like it's directed at a commenter. I think the argument --- that some kinds of ageism might not be a problem, because they involve jobs old people shouldn't want --- is toxic. But I resorted to snark and sabotaged my point.
I'm not sure what you mean, it's not so much age as things that are likely to correlate strongly with age such as experience salary expectations and willingness to work insane numbers of hours.