I wouldn't say an additional notes section at the end of article showing that is syntax is not unprecedented is an argument that the feature is ok because R does it. The author is simply giving additional context to allow readers to form their own opinion.

It's fine to not like the feature–I don't know enough about its usecase to feel one way of another–but your comment felt unnecessarily negative without adding much to the discussion.

Knowing that R users have access to these syntax and choose not to use it is interesting to consider, but that was overshadowed by your first statement.