Obfuscating username portions of the email address leads
to having subsequent parts of the address not being obfuscated;
which could mean we show someone else's email entirely.
In other words, obfuscating "john.doe@example.com" becomes
might mean "doe@example.com" is picked up by scanners.
In other news, email address obfuscation is still a horrible
usability issue and only exists to appease misguided people.