Meta confirms it is blocking EU-based users from accessing Threads via VPN

After multiple EU-based users complained about not being able to access Threads app through VPN, Meta confirmed it is blocking such efforts.

https://techcrunch.com/2023/07/14/meta-is-blocking-eu-based-users-from-accessing-threads-via-vpn/

Meta confirms it is blocking EU-based users from accessing Threads via VPN

After multiple EU-based users complained about not being able to access Threads app through VPN, Meta confirmed it is blocking such efforts.

TechCrunch
It would be interesting to see exactly how Meta is managing to block VPN users. Is it simply a matter of looking up instagram or facebook account related to email addresses used to sign up? Is it evaluating some sort of browser fingerprint? That's assuming VPN users are doing so via desktop, if it's an Android device for example is the OS itself providing information that's not getting obfuscated by the VPN?
Probably by just looking at the IP address, either due to the IP addresses of the VPNs being public or by the fact that many users are accessing the service through a single IP address