Probably more of the value is just in letting someone formulate their thoughts and write something up, instead of iterating live in conversation. Most probably

Probably more of the value is just in letting someone formulate their thoughts and write something up, instead of iterating live in conversation. Most probably need both avenues of communication available. The anonymous aspect probably makes more sense when you have more reports, but there's probably an aspect of "i can basically guess who this is, but i'm going to try to take this at face value as generic feedback to improve, instead of trying to contextualize and maybe explain it away using someone's current situation".