This is quite funny, because I feel the same about what you are saying. The way I understand you is that a seller of the product should grant any third party extensive access to that product, so that the third party can modify and implement their own services in any way they see fit. Frankly, this is completely shattering the idea of business relations as we know it. By your logic no proprietary store or platform SDK should ever exist (e.g. console SDKs should be free for all developers). What's more, extending this argument software itself should be moldable at will (I bought the app, I have the right for it to be modified in any way I please).

I mean, it's not that I would oppose this ideology in particular, it just sounds a bit radical. We'd have to change quit a lot of things for it to be feasible.