If we had access to all the data collected on us what good could we do with it, both individually and in groups?

Permanently Deleted

Healthcare would be a good one because having access to good reliable data means better treatments, especially for populations that are underrepresented in current studies

Otherwise the other data could be used for policy development. Right now when a private entity collects a lot of data, they can release the data that helps them while hiding the data that harms them. Having that available publicly means that we can develop policy based on the most accurate picture of reality

Burn it. It's ability to be misused would probably outweigh it's benefits IMO.

We could analyze the shit out of human behavior, what small things could affect us in certain ways.

Unfortunately would could only do that in general terms, since it would be impossible to isolate the specific variable we want to analyze.

But we would get some amazing data about what in general affects us.

Say, if we could compare how people who recently had a change of media consumption change their eating and exercise habits.

But we can't just select everybody who watches a particular type of media as their primary new source and tell that is what is causing them to eat more paprika or rice, that is at best a correlation, and a weak one at that.

Examples of where medical information from the population could be used for bad purposes:

• Keeping a database of people who have had abortions so you can retroactively arrest them when you change the law.
• Keeping a list of trans people so that you can find out who is partaking in illegal private healthcare.
• Searching DNA for genetic markers for autism so you can "cleanse" the world of them.

I understand the appeal of thinking that with all this medical data we could help the world and make positive change, but I don't think that's the world we live in. I can't speak for everyone, but I think most people are generally willing to give you their medical information if you can demonstrate to them that you'll use it to make the world a better place. Whereas if medical data were taken by force without consent, that suggests that you don't value your patients' agency and perhaps their other rights.

(Disclaimer: Some of these may not be accurate to real world plans (I try to avoid looking into drama too much), but at the same time it's believable to me that a country somewhere could go for them as described)

Perhaps the fetiverse could come up with some way that we, as individuals, could profit from our own metadata. 

all problems are potentially just problems with our current implementation of society.

the only thing between us and utopia are conservatives. there's a simple solution, really.