Peer reviewers need a code of conduct too

Learning to accept criticism is part of surviving the fierce competition in research. But an invitation to review the work of a peer, usually anonymously, is not a licence to patronize, intimidate or otherwise act in a way that would be unprofessional in the workplace. Such reviews are unnecessarily discouraging, particularly to an early-career researcher with limited experience of the system.
— Read on www.nature.com/articles/d41586-019-02492-w

Hell yes to this. Reviewer 2 types need to be much more accountable for their conduct and general incivility.