> the thing I'm talking about is not a person

Countries, companies, religions; hell, planets and galaxies–none of these are sapient. Yet we capitalise them.

I'll go out into the deep end for a second with a hypothesis: I think we capitalise because it makes printed text easier to scan. The words you need to spend more time on are capitalised because they aren't ones you can just roll through. This is also why the nutter affect of capitalising random words is so distracting–it drives attention to non-standard words that are, with minimum thought, being used perfectly standardly.

I completely agree with your hypothesis. And the ridiculous effect that Trump's random capitalisation has, both of making his text (even) harder to read, and of giving the impression that he doesn't actually know how to write English.

My additional hypothesis is that capitalisation accords respect, something along the lines of "this is a thing apart, something with a name, so we capitalise it". Not capitalising an actual human's name would seem disrespectful to me.

You clearly speak only one language.