I think I get it but in some countries age is not a privacy issue, business-wise. Actually, in some places (like Brazil) people expect you to disclose it, eventually. There's not much privacy protection about it like there is in US.
The weirdest is other countries where it'll be on the CV. Along with gender, ethnicity, religion, marital status, number of children(including their ages and names sometime) and a photo.
Its really uncomfortable since we're not supposed to use any of that.
Should you withhold information from your CV since some of it is known by you to not being supposed to be used by the reader of said CV?
Because CV without all what you listed is no longer a CV and is closer to a catalog listing. Should you also replace your name with some alphanumeric code? Because name can tell you a lot to discriminate on.
No not necessarily, though I wouldn't use a CV to apply to a job in the States or that is with a primarily US based organization. I just ignore the info when it comes up, it just catches me by surprise sometime.
I've actual lobbied to anonymize all applications as much as possible. Thankfully for some positions I have to review resumes for I'm unfamiliar with the cultural norms of what names are female and what are male. So in that way they are anonymized!
As with age, people are not expected to state their race in an interview, nor are employers allowed to discriminate based on race, yet this diversity report includes anonymized racial data. They could have easily included anonymized age data.