This is probably in reference to things like Dwitter.net (https://news.ycombinator.com/item?id=46557489), where the browser (plus the Dwittet-specific runtime harness) contributes significantly higher-level functions than traditional demoscene targets like DOS PCs.

It’s just a different thing. I see no “hate”, only an expression of preference for “bare-metal” demos.

Here's a 13-byte demo that runs on Chrome browsers:

    chrome://dino

It is misleading to say "I wrote X in 1k bytes" when those 1k bytes were library calls to library calls totaling 300MB.

Yeah, but it's a slippery slope, because no program runs in complete isolation. Even on the simplest 8 bit machines where there is no OS to speak of, you are still benefitting from the capabilities of the hardware - generating sound and music with the C64's SID takes a lot less bytes (and still sounds much better) than trying to do something comparable with more primitive hardware like the PC speaker. That's probably also the reason why this demo uses MIDI.

Right... on the flipside its one thing to where it is X+minor overhead inclined lib calls

Then a whole nother level of awesome where its literally just ASM

if your OpenGL driver had a glDoACoolDemo(); function, you wouldn't be allowed to call it. But if you find that among the regular functions are some code blocks that just happen to form a cool demo, you can use them and take credit for your discovery...

Probably because JS has larger runtime, in JS you don't have to write about most of the low level code. So it's easier to squeeze code in JS than in ASM or machine code.