Yes, it is true. Nobody can anonymize their data. Except for people who don't use the Internet and a phone, where can we find them today? Moreover, there are special tools that allow tracking of our devices. I've recently looked through the whoeasy complaints here https://whoeasy.pissedconsumer.com/review.html This is a reverse phone lookup product that makes it easy for you to find out who is the owner of a phone number. Maybe sometimes it is convenient and necessary.
they were even able to reproduce some of the effects using a smartphone app that overlayed parts of their deduced ID data onto a view of the world in real time using an augmented reality app