That's an illusion. Two days of location data and you can pin down the owner pretty well.

I thought about getting a SIM when Germany was about to introduce ID requirements. I quickly realized this being a moot point.

There a significant difference between "the user can be identified fairly well if you can get access to sensitive stuff" and "the owner is always explicitly recorded in a searchable database".

My burner would only be powered on for the duration of the call and the time to spin up gsm connectivity.