Once you start writing music for the sole purpose of pleasing a specific audience, or the widest audience possible there's almost no art left to it. I don't care about selling out, its more like buying in. But if we're looking at a technical death metal band and complaining that it doesn't have a "structure" or a "hook" like its a pop song you're comparing apples to sports cars and its not a useful conversation. I'd rather do whatever the fuck I want with my guitar and have my 15 hardcore fans show up than start worrying about what everyone else is wanting to hear.
My point is, any band that is succesful on a large scale, has a basic structure to their songs. There are a few bands that made it without "structure". Its not all just random noise. And isnt success what we're all after since the moment we picked up a guitar? We've all dreamed about playing soldout arenas. "I only want to play in my garage for 15 hardcore fans.." said no guitarist ever. Every guitarist can pump out some chromatic gibberish. But when writing actual music, they go to the basic structure. It has a history of success. Less is more. "If its not broke, dont fix it" applies to writing good music.
And if a tech death metal band threw in a couple repetitive hooky riffs I wouldnt tar and feather them.