[throwawayswede]

I don't really think there's enough reason for recommendation algorithms to be publicly reviewable, in many cases the algorithm itself is the most important asset of the product, and in a competitive business environment, you can't really force them to disclose it.

What would be ideal is to think of an incentive for these companies to give users an option to disable the use of their algorithm, aka natural flow. That's unfortunately not the trend things are moving, and even services that still have something like that employ dark-patterns to throw user back into their "controlled" timeline (Twitter for example reverts you back "Home" after a few days with a tiny message that is barely noticeable.)

I'm even willing to pay for a feature that "turns off" the algorithm, unfortunately that would never happen because it'd entail these companies admitting that they design their algos not for the benefit of the user but for stickiness and the dreaded "engagement", which shouldn't be a problem in itself, but then it'd quickly become obvious when they're acting sanctimonious.