[ordinaryperson]

Why would you assume they'd do one (email you) but not the other? If they're upset they're going to do both anyway, you can't stop them.

The point of this system is to get that feedback immediately instead of down the road.

You want to junk review systems completely, OK. But if you're going to have a review system, better to get that info in the moment.

I'd also add that negative feedback of others makes you (the complainer) also look bad, so there's a built-in incentive for career-minded people to be judicious in their response.