As far as I can tell, it's being tried as a pilot in the EU because the EU just made it illegal to sell people's data without explicit consent. The fee is basically "hey wanna pay us not to sell your data?", with the alternative of not paying but continuing to use the service being considered consent to sell data. I don't necessarily expect it to take off anywhere else that doesn't have such laws, though I guess if they get enough people on board with paying to avoid ads, they might try it. Either way, given that I'm blocking ads for free, I see little reason to pay for an ad-free experience.
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