Well, no. It wouldn't be the first kanji of English. Kanji is the Japanese pronunciation of 漢字 (hanzi), where 漢 means han/China and 字 means character/letter. Ergo, it makes no sense to call it "the English language's first and only Chinese character."
If you need to use a Japanese word to describe this, then 絵文字 (e mo ji; picture, character/symbol) fits better, but we already have several words for that, like pictogram or pictograph. One could argue that smileys fall into this category as well. So perhaps it's a smiley.
Learning random cool stuff like this is part of why I like lemmy, and why I used to like reddit. Please don't shut down constructive contributions with low effort snark. And before you use your line on me, if I were fun at parties, I would get off lemmy and go to parties.
There is a difference between "btw etymological this used to mean that but since X we use it in other contexts as well" and "no, you are wrong". The difference is one is fun at parties, the other is not.