An important feature of today's algorithms is their scale. Namely, such algorithms now affect billions of individuals on a daily basis. This is a critical consideration for ethics, as any small improvement of a large-scale algorithm affects positively billions of humans.
A few figures
YouTube receives around 500 hours of new video per minute YouTubePress Statista, and represents around 1 billion hours of watch-time per day YouTubeBlog-17 YouTubePress. YouTube's recommendation algorithm is responsible for 70% of views on the platform cnet-18.
In the US, the average time spent on social medias is around 144 minutes per day Statista.
Scalability requires algorithms
At such scales, content moderation by humans is extremely costly. It is also hard to uniformize Radiolab-20, which may lead to unfair treatments of different contents.