It's not that simple, both sides of the GM screen are bound by a common framework but much of that framework is providing tools for players to challenge & restrict the GM even though that's an inversion of table roles... The GM needs to be considered when creating all elements of that common framework but they are obviously not or are only being considered in the form of an assumed a hostile killer GM the players need a shield from.
DM's never use a flying creature, what does it matter if low level rogues have a ranged at will ability to drop flying creatures out of the sky with no real cost? DM's don't need to consider encounter balance or if they properly fill the adventuring day, what does it matter if wotc decides that there should be one class that remains in short rest nova design. DM's don't need to pretend there is some verisimilitude, what does it matter if yoyo healing results in PCs that make trolls wolverine & deadpool look positively fragile? DMs never need to consider things like pacing, what does it matter if the rest rules are designed in such a way that anything shy of fiat will be dismissed by simply trying again? All of those statements are obviously backwards, yet we've seen 6 packets delivering as if they are not. In addition we have not seen mechanical hooks put in place on player stuff for GM tools to interface with
