Earlier quoted context omitted.
It is illegal to not track and save this data in the EU. > If you are using a cellphone, your location is being tracked. Period. You can’t avoid it. Even TOR isn’t gonna help you. It is still possible to buy an anonymous SIM in a few countries.
I don't know if that is true. But the issue here is that the data is being sold to others for other use cases.
The SIM would still be tracked.
Don't think whatever EU laws allowed the UK to keep some SIMS anonymous have changed since they left?