The previous post was saying that Spotify could implement their own voice recognition once launched.

But that's still more than simply "Hey Siri play something by Rolling stones" or "Ok google play some Johnny Cash"

Apple should have opened Siri to spotify.

Even if Apple did open Siri up and provide a "music playing intent" for Siri like they did for messages, it would still be something like "play something by the Rolling Stones using Spotify". Is that much different from "open Spotify" and once Spotify is open "Play something by the Rolling Stones"?

Definitely yes.

So, I have an iphone 6s -- and I use Siri a _lot_. Mostly I use it when I'm talking to friends or family... e.g. today someone told me he didn't know any of Dylan's songs... and I went "oh, well let me tell you of some!"

Usually when you're talking to someone, and you spend half the time on your device suddenly disconnected from the person you're talking to, that makes things tough. Generally one should optimize for a friction-free experience. Generally, that means trying to do whatever in the least amount of steps.

When Apple refuses to open up siri, it makes things really difficult.

I mean really, this is from direct personal experience. My decision to quit spotify recently was literally this. (another was driving -- I need to go hands-free and least-steps there too for my own sake)