Minor point of information. In English "do not want" is not the negation of want. It actually means what you have defined "diswant" to mean.

That is indeed often the case, though I notice I feel hesitant to agree that this is always the case and retain a feeling that people use 'do not want' in both way, depending on the context. Regardless, when I said:

So 'I diswant ice cream' is a stronger statement than 'I do not want ice cream'

I meant (hohoho) this as a statement about my usage, not the common usage of others.

The "not" is privative here, not merely negative.

Thanks for pointing me to a further point of reference (the term 'privative').

Edit: I looked at the Wikipedia article for privative

It gives some examples:

un- from West Germanic; e.g. unprecedented, unbelievable in- from Latin; e.g. incapable, inarticulate. a-, called alpha privative, from Ancient Greek a-, a?-; e.g. apathetic, abiogenesis.

and it says:

A privative, named from Latin privare,[1] "to deprive", is a particle that negates or inverts the value of the stem of the word.

It seems like your usage of privative was excluding alpha privative, i.e. mere negation, but the examples and this summary sentence suggest 'privative' fails to distinguish (hohoho again) between mere negation and...the other thing. (Inversion? Opposition?) I'd be most amused if linguists had failed to coin a specific term for the subform of privation that is the 'active opposite' of something, and had only given a name ('alpha privative') to the subform of mere negation.

People are not being less considered

In the literal sense that I have considered these things more than they have, they are.

and precise when they use it this way. They are using the words precisely as everyone but you uses them -- that is, precisely in accordance with what they mean.

Localised examples like this seem trivial, but when generalised to encouraging good habits of thought and communication and precision, it's not just a localised decision about 'un-' vs. 'dis-', but a more general decision about how one approaches thought, language, and communication.

Also, if you just look at 'do not want'/'diswant' in a vacuum, then yes, it seems like both my usage and the common usage specify what they mean. But the broader question of using negation and 'not' in a way that cues the mental process of Thinking Like Logic is inextricable from specific uses of 'not'. I generally lean towards the position that the upper echelons of a skill like Thinking Like Logic are only achieved by those who cut through to the skill in every motion, and that less comparmentalisation leads to better adoption of the skill. And I feel like it probably intersects with other skills and habits of thought. So trivial cases like this are part of a bigger picture.