I mean, a "colorful fat choncker" website is literally the opposite of fast food - its slower to arrive, and focuses way too much on appearances.
In this analogy, the website using these ridiculous abstractions is more like Salt Bae or whatever idiotic trend has replaced him. All glitz, zero substance, slower, and for no apparent reason.
The fast food equivalent is stuff like the Google home page: it doesn't validate, is actively harmful to you, the community, and the planet but is immensely popular.
I do like your analogy tho. It is better. Most people want that trendy experience or fast food. Still, both exist because the market demands it be so despite how much it tilts a subset.
But people do notice if something just works on a subconscious level and that colors their perception of your project/brand/page or whatever. Even my totally tech-illiterate father actively complains about junk interfaces like the one at Temu. But he goes there for the sweet deals. I just wonder if it wouldn't work out better for them if the page was snappy and allowed a person to visit more product pages.
And one mistake you make is to think you need a megabyte of javascript to create a junk look. You can easily do that with HTML and CSS alone, including animations and all.
The way I see it the causal arrow points in the other way: successful sites tend to get bloaty, but they do no et successful because of it, but despite it.
And by bloaty I don't mean it as a problem if the page does a lot. Bloaty means you use a intricate Rube-Goldberg-machine to in the end do very basic things. Like displaying a popup, which can be done with a single line of Javascript, but is for some reason done using the amount of code that would result in a veritable, heavyweight book if printed.
It takes far less effort to implement the bad way. I think people take their own skill for granted. Maybe you can but most others cannot. Maybe they will learn or maybe they are happy to put food on the table and go home at 5.
Everyone else following along and merely using it I blame less, but they shouldn't have picked such a bloated library.