“Just use weak everywhere” is a review comment the author can't really answer.
The usual case is a child object holding a delegate reference back to the parent that owns it. Two comments that give the author something to work with are “Could delegate be weak, with the child just skipping the call if the parent is already gone?” and “If the child's work has to finish after the parent goes away, which object should keep it alive until then?”
The first proposes a non-owning edge and says what happens when the other end is missing. The second asks where ongoing ownership should live. They lead to different designs, and the actual requirement picks between them. Breaking the strong cycle is the easy part. Deciding how long each thing should live is the real question.
You can still disagree and reject the change outright. Swift's code of conduct asks for constructive criticism, and a precise comment is easier to defend or revise against.
