I almost wouldn't be surprised if they were going to end the show along with Luke Cage and Iron Fist. They wrapped it all way too neatly.

There are directions they could go. Like Fisk's wife surprises everyone by going crime boss to get Fisk out of prison. Or she gets killed and that puts Fisk over the edge since she was the only thing keeping him away from full Beast Mode. Or bring in one of Daredevil's many other villains.

But everyone's story arc was done, so honestly they could just cancel it.

Who knows, maybe the numbers dropped so much that they saw the whole Marvel Netflix universe as a failure, and now they want to drop them all.

Which is a shame. If the quality of the shows were better and more importantly if The Defenders were a much better mini-series, I bet Kevin Feige would have put more consideration into bringing them into the MCU, even if just for a cameo. But I don't think he was going to go near them if they didn't do Game of Thrones/early Walking Dead type numbers.