I don't mean any particular stream like Dark_humour necessarily, but mods should be qualified to mod the streams they mod

It's impossible to have a "qualified mod" rule, because moding humor is subjective and even the phrase "qualified" is subjective.
I submit memes from time to time and get them rejected for nonsense reasons. Animal crossing memes rejected from the 'gaming' stream, for being 'off topic.' Etcetera.
There's no cure for it, because you cannot use exclusively community mods or it would take 40 hours to get your meme featured.

but i want the world to be perfect. is that too much to ask?

Nope. Not too much to ask.
There's just no good way to add a qualified mod rule. After all even the best intentioned mods are going to miss some of the time.