My search told me that unless you are a gatekeeper, offering a reasonably priced ad-free tier allows to make the ad-monetized version personalized only.

I think it makes sense. Either pay, or consent to effective ads. There's no free lunch

You are allowed to serve ads, but not use data to serve personalised ads without free choice opt-in.

In theory of course, in practice nothing is being governed or fined for smaller companies.