This is honestly just inconvenient. Not something that should be changed imo.
1. The related questions section helps us find similar questions that might contain some information that may improve our answers.
2. It allows editors and mods to find duplicate questions.
3. If you are doing that, just hide the comment and it will be forgotten. However, if you are commenting things like corrections or important things the answerer missed, then leave it since it may assist those who find the question in a search engine or something.