A bit of background: Em dashes “—” (or, very often, double em-dashes “——”) are to Chinese texts what hyphens “-” are to English texts. We use them in ranges “魯迅（1881－1936）”, in name concatenations “任－洛二氏溶液（Ringer-Locke solution）”, to express sounds “呜——”火车开动了, or `“Chouuuuuuuuu”, starts the train' in English, and in place of sentence breaks like this——just like em dashes in English texts. They are so commonly used that most Chinese input methods map Shift+- (i.e., underscores “_”) to double em-dashes. So, as a result, while I see many English people have to resort to weird sequences like “Alt + 0151” for an em-dash, a huge population in the world actually has no difficulty in using em-dashes. What a surprise!
As for this article, obviously it was translated from its Chinese version, so, yeah I don't see em-dashes as an AI indicator. And for the weird emoji “” (U+1F54A), I'm fairly certain that it comes from the Chinese idiom “放鸽子” (stand someone up, or, literally, release doves/pigeons), which has evolved into “鸽了” (pigeon'ed), a humorous way to say “delayed, sorry!”.