If I am not wrong, this is what both Facebook and Apple trying to do. Both these platforms can sell individual articles but they choose not to do so due to high overhead in the payments infrastructure.
The problem in such a model is that the negotiating power of the publishers is much lower. And hence, they are always at the mercy of these aggregators. And I believe that will be the natural tendency of the aggregators, since they control the distribution.
Platforms like Scroll & Magzter are still in early times while Facebook and Apple are way ahead. All of them will invest in algorithms to surface personalised recommendations for users. They can easily tweak the algorithms to lean the way they wish to & the motivations will not always be clear since customers don't have visibility into their recommendation algorithms. And this will have a great impact on the Publisher since their revenue depends greatly on these recommendations favouring their content.