You have to think,alot of artist of today don't get credit for being lyrical,witty and having wordplay because they have country accents.
Sadly the world equates having a country accent to not being intelligent. If an act like the Migos weren't so country,and were rapping about the boroughs and holding the llama? Or rapping about 64 Impalas and pronouncing their words with hard 'ers hiphop fans would be all over them as the second coming of Wutang and NWA. The drunken beligerent delivery is actually what hurts much of the newer generation. It's hard for me to look at a guy like J Cole and Wale and say he is more talented then the Migos lyrically outside of his content.
But because he has a more coherent,kind delivery,and positive content,its seen that way. Lack of content is what I think you mean to say OP,and yes they are all very lazy in that regard.
Has nothing to do with "country accents" IMO. Lil Wayne, Outkast (Big Boi & Andre 3000) 2 Chainz, TI, Scarface are lyrical southern rappers with country or southern accents. The reason no one rates or categorizes the Migos as lyrical group or MC's is simply because they're straight
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