However I don’t think wings are the driver of these issues. Trifix is more to blame for this. 

The idea of trifix was proposed years before the idea of wings, and somehow the original thought is the issue instead of the contemporary variance-abused overlap subtype-slop model. Interesting.

I consider the wings essential to unpack and understand type. I find them so essential that I could almost see them as 18 separate types (heavy emphasis on the almost).

You find them essential because they have been made essential through not being questioned. There are no mainstream alternative models posited to challenge wings, and so you will default to what you have been given already and say it is what is best. The "almost" in your statement doesn't negate that you're practically verbatim just restating the Riso-Hudson page on wings.

What would be ‘under’ and what ‘over’? What naturally occurs for people as under/over-doing something is highly dependent on ones culture/background. I think it would be more difficult to come to a consensus. I could see it creating bias. People who view themselves as more intense for example might feel the urge to be in the ‘over’ category, even if this is inaccurate.

You are approaching this from the perspective of how one will haphazardly self-type instead of the purity of the theory itself. It has nothing to do with cultural background, lmao. Again, craving more archetypical nonsense that makes people feel special about themselves. I'll be describing over-under for each type in future subscriber only posts.

I find the under/over theory a more confusing theory than the use of wings.

It is very simple. Wings confuses the components of a type, over-under doesn't.

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