If they didn't wish to go ad-free, they could browse different things to move their ad bubble around.
I would be happiest when the ads I get are way off target and the people LinkedIn suggests are complete strangers.
The latter I've never really managed, but the former is not that difficult: at one point my ad stream consisted largely of luxury condos in St. Petersburg and bank accounts in Cyprus.
I took an online hearing test long ago and now ads are convinced I'm a fair bit older than I actually am. I'm not sure what would be most effective to get the trackers to assign a younger cohort, but in imagining generational browsing tells, I suppose cartoon nostalgia is probably one of the best proxies for birth year/location.
(In the pre-internet days, discount magazine subscriptions were one of the inputs to marketers' lists. Bernays describes the use of segmentation in WWI propaganda.)
See also https://www.tandfonline.com/na101/home/literatum/publisher/t... . Böll worked in a statistical office, so he's well aware of how little the narrator is Sticking It To The Man, but despite that depicts an example worthy of emulation.
> I'm not sure what would be most effective to get the trackers to assign a younger cohort.
Start searching for contraceptives and within no time you are not only 15 but also female.