It still is a challenge to find the right words in code reviews, no matter what side I’m on:
As the reviewer I want to give really good reasons, be persuasive but also signal that I know that we live in a contingent universe. If I have knowledge to give I want to explain things well, without coming off as paternalistic.
As the reviewed I want to be open minded, interested, but also being able to challenge things back without coming off as defensive.