I’m wondering if cats think of us kind of like how a person thinks of a friendly bull: aware that they could easily kill us, but not necessarily afraid of them; or more like a large Dalmatian: they could fuck us up, but most of us don’t really think about that unless they’re being aggressive.
I grew up with dogs and feel like I understand them a lot better than I do cats as a whole. I adopted my cat almost four years ago and I feel like I get her pretty well, but I don’t really have an idea of what she thinks about me. I also don’t really know any other cats, though I’ve gotten along with strays and friends’ cats a lot better since I got mine.
Cat tax:
We do the same when scared, and at least in our case it's outright useless. And more importantly it isn't a conscious reaction, so it's really hard to associate it with the cat potentially assessing the size of the threat and trying to make itself look larger.
Also note that they'll also do it when they feel threatened by a smaller critter.