Netflix needs content which results in the maximum number of subscribers at a given point in time. Which has some correlation to eyeballs but is very different from networks selling ads based literally on eyeballs (and their demographics).

This requires some combination of quality (whatever that means exactly), pop culture relevance (Squid Games), and good enough filler so that less selective viewers don't run out of stuff to watch. Of course, they can program for niches more than traditional broadcast TV did too.