If I build a robot that shoots a man when I press a button - and I press the button - then I am still to blame.
If I build a robot that runs a bunch of algorithmic code and it shoots a man - I am still to blame.
So the orginator of the algorithm (Facebook) is to blame, in full and without reprieve. The algorithm did not exercise free will.
Had Facebook made it so that the algorithm was transparent, or at least easily disabled then they might have some defense. They did not do this.
Obviously, if you build a killer robot, it's totally okay as long as you have no idea how it works.
The thing that's opaque is this function that the program produces. You can really only know how the function works experimentally.
If you buy a handgun, and sometimes that handgun goes off without the trigger being pulled due to faulty design, then that's the one time the handgun manufacturer is actually liable.
It's not as if you get to tell the algorithm "Hey, I want Facebook to be a positive experience" or opt in to content.
When you have an interest like religion or politics and the algorithm starts showing you anti-vaxx material, that isn't the user in control. It is more like that faulty firearm.
For a handgun both factors are widely understood in the majority of the adult population.
Youtube doesn't particularly have this type of problem, for example. It has others, sure, but the core content it breeds is not shorts of high schoolers in their bedroom dancing in their underwear. Snapchat and sending that content privately was one thing but now tiktok validates that behavior with a public audience. And then onlyfans exists to graduate your content and monetize your body directly. I’m pretty sex-positive so it’s not that I’m turned off by the concept of people wielding sexual power in society or making money off their body. But I’m not sure what society looks like when that’s the highlighted path for 16 year old girls to replicate in order to make life changing money or be immensely popular as their own brand in their 20s.
Back to the youtube example: on youtube it seems the content is important because you have to engage for more than 30s whereas on tiktok it feels like you’re following personal brands and the utility of the content is almost irrelevant.
So in this case who exactly is to blame ?