This analysis and comparison to ancient glyphs completely overlooks how emojis are tied in to technology manufacturers and therefore their profit interests. Emojis have been a major driver of the planned obsolescence business model. iOS (and even Android before version 12) requires a full operating system update if you want to get the newer emojis; eventually, that means having to buy a new Apple device. The constant addition of new emojis (and their essential role in social media) is one of the many pressure points that Apple uses to get their existing users to buy new devices.
One big problem with this interpretation: expressivity is severely limited with computer text compared with handwriting where you can do what you want, and Unicode is about encoding what already exists, not creating anything new. You could say things like emoji skin tones are an exception to that rule, but modifiers are very limited in Unicode due to how it’s all implemented, and can’t develop in the way described near the end.
I think the color variations and joining characters should be allowed without limit or reason, and up to the font if it wants to support an amalgamesh of fifty five different “people” emojis in twenty colors.
It's just a lot slower at invention than a scribe can be.
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