I don't doubt that Samsung makes a good product and, by providing viable competition to Apple, forces Apple to do the same. However, the difference would have to be substantial for me to walk away from my iMacs, MBP, AppleTVs, Apple Watches, iPad Pro, nearly 400 iTunes movies, thousands of iTunes songs, etc. as that ecosystem works very well for me.
I understand.
I thought the same thing too, that it would be difficult for me. But it wasn't (although the Apple Watch would be an issue if I had one).
The deal is that my phone is not the center of my Apple universe, like the iPhone is meant to be now. Once I switched, I found my phone to be the equivalent of a mini computer that I could treat as a "second PC." I simply couldn't do this with an iOS device, especially the iPhone.
All my Apple-related music is there (aside from the stuff that is on Apple-lockdown), and syncing just means using services other than Apple's, which is good for me when I'm away from my all-Mac universe.
So I gave up the "easy" integration for the ability to not have to bring a laptop with me in many situations, just the phone. Power over convenience, I guess.