For some situations, it helps to have multiple accounts on the same website while making their IP address and user-agent metadata different using Tor or similar.
I think that won't be easy anymore. Most people have just one phone. If the same phone is used for all accounts, it's easy to associate them to the same person. Technically, it may be possible to anonymize if the authenticator goes to great lengths to implement it. But we're talking about companies like Google here and I don't see them doing that.
(Happy to be corrected if I have misunderstood FIDO.)
I think that won't be easy anymore. Most people have just one phone. If the same phone is used for all accounts, it's easy to associate them to the same person. Technically, it may be possible to anonymize if the authenticator goes to great lengths to implement it. But we're talking about companies like Google here and I don't see them doing that.
(Happy to be corrected if I have misunderstood FIDO.)