I remember years ago someone talking about the idea of "open algorithms" in the sense that for any given platform the sort algorithm itself could theoretically be made available for users to submit and share their own custom sorting implementations. A company could just release some DSL of config setup that would make it possible to tweak your own feed. Even if this was tricky, you can image users that were more technical creating algorithms that other users could apply.

I understand why this never happened (algorithms are, after all, optimized to the benefit of the company, not the user), but still it's a shame that this was never explored (at least not to my knowledge).