I didn't absolve the creator of guilt, I just said that it's unlikely they're intentionally trying to make her sad. They're just trying to increase engagement - at any cost.
Exactly. These outcomes are the results of the algorithms and their tuning, whether intentional or not. Humans are responsible for it and can tune it differently, to a different result. However, these new tunings may reduce engagement or other profit drivers, which a for-profit company will obviously not want to do.
There is no algorithm acting independently. The responsibile agent(s) is(are) a person(people).