Ah, this is nice. It brings the Apple Hide My Email functionality (though not compatibility) to all platforms, which is something I do desire since using Hide My Email makes non-Apple platforms unusable for logins.
Why would using Apple's Hide My Email functionality make non-Apple platforms unusable for logins? If you're storing these credentials in a cross-platform password manager like Bitwarden, you should be able to enter your (fake) email address and password anywhere to sign in.