That's because Google forced manufacturers to go with a modular design since 4.3 and it is starting to take effect. Core components can be updated on the fly now with little testing and work. I actually talked about it heading that route and how it would be better for Android. To get Android licensed to use Google services you need to comply with Google's standards. They should have done this a long time ago.
That shows what I have been saying you know. How is Samsung going to fast track security updates if they have to wait for carriers to approve updates?
See, now it sounds like you and I are on the same page! I too would love it if carriers were simply bypassed for these sort of updates. This is exactly my point, if the carriers got out of the way this would be so much better!!!! Like iPhone service for Androids!
Don't you see???? Verizon IS the problem! 
I wanted to add...
I am a firm believer that manufacturers should be liable for everything and consumers should hound the manufacturers. The reason why our system is broken because we always go after the carriers. In Europe they do how I say it should be done, and they get far better support. They go through the carrier testing(Yes they do this), they go through ITU testing(similar to FCC testing), and they can also buy under contract. I am willing to bet 10M+ customers hounding the manufacturer for an update instead of the carrier would move things faster 
Bring back the art of boycotting.
