"Whose problem is it that it solves?"
It's possible to get some benefit from an algorithm/process, just as a side effect, that was never designed to work in your interest and is an opaque cloud service. Maybe the service is solving the network owner's problem of selling you to advertisers. If you want to maximise for "interest and relevance to my life goals" there's nothing to stop you running your own "algorithm" of course, except any obstacles put in your way by the data network owner. For that reason it's more important to pay attention to the freedom of the network (open API, federated, maximally distributed etc) than the algorithms that run on it. If you control the former you control the latter. HN (the network) seems to allow a lot from the plethora of viewers I've seen.