Core Web Vitals (CWV) scores are taken directly from the CrUX “real world” data. And CrUX only gathers data from Chrome browsers (Desktops and Android phones).
So shutting down 3G in Germany will only have a major effect on your own CWV if…
- the vast majority of your visitors are in Germany, AND
- The vast majority are using Chrome or Android devices.
Check your Google Analytics…
- See where your visitors are located? In Germany, or from distant countries with weak 3G or even 2G service?
- See what devices they are using? Androids or iPhones or cheap-phones? Remember that only the Android phones will count towards your Core Web Vitals score.
My site serves the US and most of my mobile visitors are on fast iPhones - but they don’t count towards my score :@