I agree with your sentiment. However, I think the truth is the various owners are trying to balkanize the field of movies. They aren't going to license their wares to Netflix at any reasonable price. I think Netflix spending more on in house content was looking ahead to combat that problem and protect their business.
I don't know that they've spent wisely on their in house shows/movies. They seem almost good enough. Not really satisfying. And leave the impression with some, "this could have been a really good movie, but wasn't quite up to par". I'm not sure how long I'll keep them either, but I've been thinking that for about a year.
I had hoped by now theatrical movie releases would stream from some source the same time they are released at theaters or a very short time like one month later. With large TVs and good sound at home, going to the theater isn't very attractive. This would work most efficiently if some company or small number were clearing houses for this to happen. Netflix was well positioned for that. I think it would leverage their advertising for new releases so it could drive additional sales that are being left on the table. Of course stodgy greedy media companies will be slow to come around if they ever do.