I think in general the demoscene is more heavily weighing technical excellence. Ie the audience is expected to understand and be awed by that, more than the artistic part, though the latter can be important as well.

I also thought demos are supposed to be small self-contained binaries, has this changed?

There are and were all kinds of competitions. The wild category is probably the most obvious one regarding no size limitations, but the generic "combined demo" category which is very often present at competitions is also usually without restrictions (but it must run on the competition machine).

See http://www.pouet.net/prodlist.php?type%5B%5D=wild for wild demos (e.g. https://www.youtube.com/watch?v=LCIsIfEOEI8 :)) or http://www.pouet.net/prodlist.php?type%5B%5D=demo for "combined demos"

OHP Mega Demo 9000 is one of the greatest things to come out of the scene.

Fun fact: In the famous HBO "spinning chrome logo" intro ( https://youtu.be/i1NKoMNy5bY ), the sole use of a computer in generating visual effects was to control a servomotor that slid one patterned transparency over another, much like this demo, to create a "starburst" effect (seen just before the logo itself appears).

I would say creative coding is more artsy and less about breaking "the known limits".

When talking about steroids I would claim if so the sceners take them :D

Steroids, no.

Amphetamines (or as I like to call them, brain roids), maybe.

Yeah, I meant it more in a metaphorical sense. I don't think many artists are as dedicated and to some extent extreme as sceners. I think one guy of Farbrausch got a heart attack on a release party. Sceners seem to seek crunch time...

you say that like its a bad thing.