IMO there are many solutions, but two very basic things can fix these problems:
- Make users pay to use a service so it is ad-free or ad limited so that there is not an incentive to hold a user on your platform as long as possible
- Remove public facing metrics such as likes/views unless absolutely necessary. When necessary, make them a harder UX to get to so that someone without the need cannot easily access them.
People keep saying the model won't work, but when you look at ARPU for many of these services, many people would gladly pay that. People always frame it at replacing ads, but I think it's much more than that - it's making the experience of using the platform itself better by removing a lot of the incentives that cause bad mental issues with social media.