Maybe, maybe not. They record 3 octets of your IP address and the experience is opt-out rather than opt-in. ECJ ruled that IP addresses are PII but did not specify if using a partial address is OK. On the basis it is the 3 most significant octets, then this could be used to identify a company or a pool of users or a unique user on an unpopulated network.

Edit: also from [1]: "Hashed MAC address — Determine a cryptographically (SHA256) anonymous and unique ID for a machine. Useful to determine the aggregate number of machines that use .NET Core. This data will not be shared in the public data releases."

I think a machine could be a user in this circumstance? Also a hash isn't anonymous if it's idempotent based on the IP address alone as it's merely a derived value.

[1] https://blogs.msdn.microsoft.com/dotnet/2017/07/21/what-weve...