Actually user, the alignment system is literally an active force that makes all sentient beings adhere to a set of stereotypes.
When people go against this system, they end up dead, or thrown out of the D&D reality entirely, and end up as Vestiges, or simply cease to be.
Deities literally get saves against this, and most are not even aware of it, except for Pelor, hence his grey Knights.
Allegedly, the Alignment system is held up by paragons of each part of the spectrum, and if they go, the system goes, but without the system, Demons, aberrations, and a select number of Far Realm natives would be able to exist as they were, which is that "Above all your crap" eldritch horror bullshit, and these things get defaulted to CE to offset their actual Intellectual high ground features.
If you've played D&D enough you'll have noticed this immensely, Lawful evil sounds good, but the evil part almost seems unessary despite providing results, LG's are basicaly YHVH tier assholes, CE's want out of the universe are are reduced to psychopathic nihlistic asshats with self destruction in mind, and CG just is a gateway to a slippery slope.
The Egyptian Pantheon came from earth itself but KEK isn't present because he literally cannot exist in universe bu tthe collective meme that spawns him lays dormant, and this is why the Slaadi final evolutionary form is literally a Black Slaad, because it's the Darkness before the light, but the False laws in place prevent it from moving forward.
Technology in D&D is completely stunted because of the weave, and every instance of progress is shut-down completely
Even the fucking Outer Gods and Great Old ones are denied access and work through proxies to unravel this system, as it's a universe that Yog-sothoth doesn't recognise and thus, under his all too-common statement, means it doesn't exist, it's an orphaned reality.