Not all of them use proof of work and verifying transactions have value.

How does it work?

Blinkit always feels like it's too good to be true. I'm hoping they're not just burning VC money and they end up with a viable business model.

True. Not much even the platform can do about that. They're all just impressions to the model.

I'm sure the objective function considers dislikes, unfolllows and not interested. I've observed though that most platforms are comfortable accepting a large amount of negative signals to get engagement

Likes/dislikes are always a major feature in stream ranking. I agree that the users have a big role in choosing what to engage in but it's hard to be mindful when you're just trying to relax.
Social media companies should be more responsible in balancing the user's needs.

Is this real?