Character "⧸" (
https://www.compart.com/en/unicode/U+29F8) is way harder to distinguish from "/" than ん.
That said, looking at image depicting a phishing mail in the article, I notice that hyperlink text looks like legitimate link, while the link itself points to the bad site, and I would expect this alone to be extremely effective. Many people, myself included, would probably not bother hovering on this kind of long link to confirm it matches the text.
