We as human often personify other things, although what we perceive has nothing to do with it.
Yep, agreed. We absolutely do-do that more often than we may realize generally for sure aye.
Though my agreement here is to the extent in so far as assuming that your usage of 'perceive' might possibly be strictly associated with the 5 physical organs of sensory perception only-(ie: sight, sound, touch, taste & smell)-and if so, would be quite different to how I typically use the term to more broadly reference the standard 5 physical senses but also non-physical sense perceptivities as well, eg: empathy, intuition & so forth.
Note: the communicative differences between people and most social animals.
Ie: we generally don't pay much attention to body language whereas most social animals use body language as one of the primary means of communication.
My cat does some weird stuff, and at times looks at me with scorn, like the "i would eat you if you died right now look"....but then he comes over and rubs is face on my leg...............

Shit, the interpretation of a scornful expression may actually be quite accurate, but he probably wouldn't tuck into ya corpse unless he was starving and unable to find any alternative sustenance.
(Despite what sensationalist cat "experts" claim)
Whenever he gives you the pissed off look, it'll be because he wants—or rather expects your immediate attention.
(*Imo unlike dogs who typically conform within a pack hierarchy with each other and with people as well, cats on the other hand-(hypothetically mind you)-probably don't consider us in any hierarchical sense at all and maybe more like they reciprocally interact with us based on how they regard an individual's standing relative to themself within some sort of animalistic meritocratic view perhaps.)
Nugget's 'booping'-(*ie: rubbing his face on ya leg)-could be either or both communicating his affection for you &/or may be him attempting to gain your attention &/or 'herd' you-(*if done while you're walking around and especially if he seems to be actively getting under your feet, that might indicate he's possibly trying to 'herd' you towards something in particular that he wants.)
The following you around behaviour would indicate he likely regards you as his #1 favourite companion and he probably also likes to be kept in the know about whatever you're doing.
*Disclaimer:

I certainly ain't no cat behavioural nerd and am mostly just guessing here.
In this photo, his bitch-ass kept getting on the counter and before this picture was taken, I removed him from the counter at least 10 times, in the last 2 mins. Each time, he would step on my keyboard, and look at me with a certain look. The one in the picture was one of maybe 5 different looks.
Did he think that by looking at me a different way, the result would be different, in that maybe I would allow him to stay on the counter................not like he gives a fuck.
Does that make sense?
Yeah man. Makes sense.
When Nugget gets all up in yo face while you're doing stuff like using the computer, it'll be him wanting your attention and wanting to participate.
If you try imagine from his pov what he sees when looking at you tapping away on a keyboard while focusing intently...(just my guess)... Nugget maybe assumes you're playing some strange game-(ie: but in a cat's mind keyboard tapping may be loosely equivalent to how cats arbitrarily whack shit around)