Overall, your message seems to be that we shouldn't try to do anything about ageism. Try to be immune to it (1), or try to fake being young/childless (3 and 5), or get what you can despite it (6). Just as a thought experiment, consider how that would sound if we were talking about race, gender, or sexual orientation. Then (3) is like saying that people who aren't straight and white and male should try to minimize their differences from that "ideal", and (6) sounds like only companies that can't hire enough SWMs need to consider anyone else. Would you also promote skin-lightening or breast-reduction surgery to because they eliminate "obvious tells"?

Age should not be the one bias that's still acceptable, and that we can't talk about fixing. Advice about how to live in an ageist world might be pragmatic, but telling people to accommodate it at all costs is practically the same as condoning it.