I agree that a good chunk of it is socialization and stigmatiization driving and reinforcing thought modes that persist throughout life, but I also think that a large majority of NTs do not consciously think before they speak, the way they process social situations is largely un/subconscious, automatic, closer to breathing/blinking than to walking or origami, and they literally cannot fathom that for others, socialization is a much more explicitly conscious, intentional, and active process.

A large subset of the population literally does not have a consistent internal monologue, ie, explicit, active linguistic thought processing of the world around them, and basically cannot imagine what it would be like to just have that all or most of the time. For those people, that's not a default mode, its basically a demanding task to perform.

https://www.psychologytoday.com/us/blog/intersections/202304/inner-monologues-what-are-they-and-whos-having-them

https://www.iflscience.com/people-with-no-internal-monologue-explain-what-its-like-in-their-head-57739

https://www.verywellmind.com/does-everyone-have-an-inner-monologue-6831748

Roughly 30%-50% of people have regular inner monologues, meaning roughly 50% to 70% of people don't.

Those are the people I am talking about, for whom constructing an actually logically consistent and linguistically precise thought is basically an uncommon and exceptional task of mental labor, as opposed to... a default operating mode that happens almost all the time and for which it actually takes mental effort or some kind of conditioning to not do that, or to moderate it.

I think theres more to it than just socialization.

Nearly 1/2 to 3/4 of people where an inner monologue seems like a fantastical, made up idea, an uncommon task to perform?

That seems to be way too many to be from socialization alone, that seems to me to have a large 'nature' component.