I am bothered by how "discrimination" has become an inherently offensive word. Choosing an employee among many is by definition an act of discrimination; what matters is what you base your discrimination on - whether it's something relevant to their role or not.

Mere lexical conservatism? Not quite. Policy discussions should revolve around which type of discriminations are permissible and which are sufficiently harmful that they should be banned; but the "discrimination = bad" has made this step all but impossible.

Hence you get people honestly, and correctly, arguing that to favour younger, or older, people is a form of discrimination. But then, rather than asking "did this employer have a legitimate reason for preferring a particular age group for the job?" (hopefully followed by "is it going to be harmful if people keep doing it?" and "do we have the means to stop it?"), they just slap the label "ageism" on it and are convinced that they have just proved that it's a Bad Thing®.