Yeah frankly even Netflix isn't great for 4K content. Most of the big blockbuster and good movies not available in 4K. Yet you get 4K for crappy standup comedies or freaking Adam Sandler movies again and again.
Too bad, pretty annoyed with Google Play movies as well. My first 4K TV, a Samsung 8000 Series from either 2017 or 2016, Google Play won't stream 4K on it at all even when I paid for 4K movie... total BS.