There are at least two, though they may not be relevant for everyone: POSIX compatibility and ubiquity on random systems where your ability to install things is limited.
This is what YouTube's Subscriptions tab does and I hate it. Rarely uploading quality creators are hidden in a sea of daily uploads from channels which focus on regular uploads rather than quality.
I think there is a place for a smarter algorithm than "ORDER BY date DESC", but one that is not designed to manipulate users into addiction.
I'd say that it is the internet in general that has a spam/scam problem. Due to bandwidth costs, which apparently only Google is able and willing to subsidize, YouTube is basically the internet for videos. Many opinions I read about YouTube do not consider this point and treat it as just another website. But for me, making Google responsible for whatever is posted on YouTube is akin to making ISPs responsible for whatever is going through their switches.
YouTube has a lot of problems, but I personally have no doubt that its existence is a net benefit to humanity. Calls for tighter regulation (or breaking Google down), which appear to be more and more common these days, make me wonder if would even have an alternative if YouTube went down. It is easy to take it for granted.