Browser fingerprinting: "Your unique combination of extensions/settings makes you identifiable among other users."
Service anonymity: "There are no other users to compare you against because we don't collect identifying data."
When you sign up with just a random 32-char string, there's nothing to fingerprint. No email to correlate. No IP logs to analyze. No usage patterns to build a profile from.
Fingerprinting matters when services collect behavioral data. We architected our way out of having that data to begin with.