I worry that such projects can never make a dent in Facebook because from their very premise they embody moral zealotry.
You can't have an app comparably or more habit-forming for our reptile brains than Facebook without engaging in more than a few of what was relegated to be called "dark patterns".
Should it refuse to do any of these, it is losing further footing against a platform that everyone is already on. The absolute majority of people have no conscious control over their habits, and ain't nobody on a global scale using a Pavlok or other shock collar to get them off Facebook and onto a competing platform.
What CAN be improved, to give it an advantage, is twofold:
The censorship is straightforward: Facebook's deletion or shadow-banning(hiding) of content is done to cover Facebook's ass legally. If it was for a more pleasant experience for the viewers, there would be options to view this content, hide it until clicked on, or hide it entirely. Furthermore, the posters of the "offensive" content would be catered to, not banned from liking posts and even messaging their consenting long-time friends(and businesses, too) for several days at a time with extreme prejudice. A most ridiculous policy.
The other component is the echo chamber effect, the siloing of opinions. Of course deeply unethical, it may be percieved to improve user experience by presenting content users agree with. I feel like that is a deception, caused by a misoptimisation - Just because we didn't like something or comment on something doesn't mean we didn't have a visceral reaction. Clicking on links and sharing links to posts in messenger should definitely affect post relevance.
Maybe also throw in a popular post from an opposing demographic.
There is a lot of low hanging fruit here.
From performance, feature parity between platforms, and data usage, to features like corellating multiple uploads of the same image, including screenshots and better search.
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