GDPR works, but only where someone enforces it

This study measured tracker connections on globally and locally popular sites across ten jurisdictions and found that strong regulatory enforcement (notably in Germany and Spain) correlates with substantially fewer trackers, while countries with opt‑in laws but weak enforcement show tracker levels similar to opt‑out jurisdictions. The research highlights that advertising and analytics dominate tracking, a small set of parent companies and consent‑management vendors shape behavior, and many sites selectively geofence compliance (the so‑called "Brussels shield"); it also notes measurement caveats such as server‑side sharing and fingerprinting not captured by the crawler.