I'm optimistic that "what it could have been" is what it will eventually be. Originally there was just Apple, and their lock-in driven business model. Competitors could emulate them and still get away with it for a while, but it will get commoditized to the same level PCs are at some point.
Funnily enough, originally people thought it was Apple who commoditized mobile computing and software development by getting it from the clutches of telecom providers
I will say, at least after Apple introduced the smartphone to the masses we did eventually get some amount of commoditization and control as consumers. Not from them, mind you, but they successfully killed the old giants in their bid to take their place, allowing Android to rise and give some amount of control to the people.
I had a buddy who was working on a Linux base for Motorola phones back around 2004/2005. I mentioned this to a EE I worked with back then, who had spent a long time working for Motorola, and he said the carriers "would never allow it."
Having the baseband firmware cordoned off was inevitable
