Technology

GDPR doesn’t say you can never use any form of user data. It says a lot about what data is considered personal, what kind of disclosure and consent you need to setup first (mostly terms of service stuff), how you can store that data, how you can use it, and what responsibilities you have to remove or produce a copy of that data on demand. Until you’ve implemented GDPR it can be hard to understand what it is. But it’s not a super bonus +1 magic shield for all information.

No.

Netflix logging your IP is the equivalent of taking a photo of someone in public. Not ideal if you're into privacy, but it's a public place, so it's your problem. YouTube's Adblock detection is equivalent to patting them down to see if they have a weapon and requiring their ID. The software actively looks for changes, using technology that could detect what extensions you have installed, gather data to profile you better for ads, and monitor what you're doing in your browser while the tab is open.

Both are ultimately for the same purpose, to prevent people from avoiding to pay them, but methods matter.