Ultimately I think Disney/Marvel is on a hot streak with the movies and they don't want to fuck that up by being too closely linked with shows that are nowhere near as popular. I mean they even keep a comfortable distance from Agents of Shield, and that show is firmly grounded in the same universe.

But more than that, yeah, the events in Infinity War would have rocked the Netflix shows to the point where they all would have been just about the Infinity War aftermath. While I think that would have been fun, and far more interesting than a few vague references to "The Incident" I could see how that would be frustrating for writers that want to tell their own stories or bring their own vision to the table.

Still, damn. A Luke Cage or Daredevil cameo in Infinity War would have been great. Even something minor, like Luke is beating information out of Turk and Turk suddenly disintegrates. Or Daredevil is beating up a gang of dudes in a hallway and they all up and turn to dust. Then their own shows depict the fallout, where everyone in New York is trying to adjust to the idea that half the population just disappeared out of nowhere. Although I'm sure Avengers 4 will make that even more complicated with either time travel, alternate timelines or some magical shit to bring everybody back, which would be even harder to explain in the later seasons of the Netflix shows.