They look very different than their counterparts constructed from text. Also, many of them cannot really be constructed with regular characters.

People also have been adding smileys to their communication as early as the 1700s.

Because language is use. Billions of people use emoji in their every day textual communications. Unicode exists to encode all textual communication.

Emoji symbols don't emerge from language use.

Corporations like Apple, Google, IBM, Microsoft, Facebook invent them. And pay tens of thousands a year for Unicode consortium so that they can vote to add them to the standard.

They are corporate symbols.

Emoji were in widespread use in Japan on the mobile phones of the generation before the smartphone. That is a corpus of many years of human communication which falls within the goals of Unicode to unlock. Those emoji may have been invented by AU, Softbank, and NTTDocomo, but they exist.

The recent additions come from a variety of proposals; most seem to be independent initiatives.

Big tech embraced emoji, but they got in the standard without them. Their widespread use was pretty much a given.

Corporations didn't invent "them", but they definitely control them. Never mind the consortium, it's the corporations themselves who actually create the drawing that we see. And they definitely also created the typefaces that we use, like Times New Roman.

But overall, I don't think something is bad just because it's corporate. Do you think this is a bad influence of some sorts?