My previous question revealed that the context for 本人 should be much more formal than I thought. Below is an example from last year’s 閱讀課:
Is this guy trying to impress his potential landlord with his mastery of formal language and ongoing PhD? In my native languages, informal language would be OK! I asked my teacher the same question last year and her opinion was, you didn’t need a formal context, as long as it was written. I suppose some deep mystery is hiding here, not easy to grasp for 老外. Perhaps I need to understand what “formal” means to Chinese.
Next, an example from the Internet, taken from here and a google plus profile:
Is this due to regional differences? Can Taiwanese natives please comment on whether this is natural to them?
A further example from the internet, found here, seems to start somewhat formally and then finish totally colloquially with 求計算機大神導致:
Perhaps 本人是⋯ is a special case? Because this platform seems full of it: