Because corporations don't give a flying shit about your data and it could end in the wrong hands

One problem is that you don't know who's actually hoarding your data and for what purpose.

Let's flip it. Why do people want data on you? why are people willing to pay for it? or governments deploy threats of fines (backed up by men with guns) or men with guns in order to force it's collection on you?

private companies feel like they can make money with it, that they can make you do things that are profitable (buy something you wouldn't, vote a certain way, decide against insuring you etc). Are you cleverer than teams of academics? I'm not.

Governments want it to enhance control. Sometimes that control can be benevolent but it's still control. Often it's not benevolent, selective enforcement of unjust laws against political opponents etc.

So why surrender privacy?

Privacy is important everywhere, people most often answer this question regarding digital privacy, but think about in your everyday life. For example, I just bought a house. Buying a house is public record here in the states. The moment you buy a house companies will grab that data and then start trying to sell you services. They will use the name of the bank that you took out a loan with, they know your loan number, loan type, loan amount, full name and address. They will do everything to misrepresent who they are as if they come from the bank that holds your loan to sign you up for some service you most likely don't want or don't need. Older people fall for it all the time. Digitally it just gets worse.

I didn't authorize a random company to have access to a treasure trove of data about me so I have to lock everyone out. If data about me is being sold someone is making money off my private information. Ads can and do contain malware and consume extra data which I again never agreed to.

These are very basic arguments but I hope this helps.

In principle, anthropologically speaking, the depth and breadth of data that has been collected is at its face outstanding and valuable. The full range of human experience is documented. What can be learned if it were studied would perhaps help save the world.

Unfortunately, that "public" data is only available to the companies that harvest and buy it, not to the world at large. Not unless you are already in the shit that is collecting information on you

To echo what other people have said, any benefits of public data is immediately squashed by the heinous abuse of power that comes from not protecting privacy.

Information is freely given by those who care about the world and want to see it improve. No need to take away human rights for that.

Because I find it unsettling on a personal level when my wife and I, in the privacy of our home away from the world have a conversation where we make a joke about buying a banjo, and then every day for the next three weeks everywhere I go is flooded with targeted banjo ads. Verbal conversations, away from everything but our phones and computers.

Because I find it unsettling when I go to a site I have never gone to before and it greets me with my name and already knows where I live with the shipping details even though I clicked "I do not consent" on every data pop-up that I've seen in the past five years.

Because people are selling that data, my data, data about myself, and I get none of that profit and it was done without my consent or knowledge.

Because a company having my information should be something I need to personally allow, not something I need to ask and beg them not to obtain.

Because I can think of very few, if any, benevolent purposes of using that data, but there is a legion of malevolent reasons for it, and of the ones I have seen, all of them fall into this category.

All this being said, I should not need to have a reason. The onus should not rest with the individual to prove that they deserve undisturbed privacy, it should rest with the institutions that want this information; that it is a requirement to obtain this information for valid reasons and not frivolous ones, or ones rooted in greed or ideology. Like a search warrant for example.

The shift from "You have nothing to hide if you aren't doing anything illegal" to "It is illegal to criticize us. We will keep an eye on you to make sure you don't." can happen a lot faster than people want to realize.

https://lemmy.world/post/2338283

If the data was truly publicly available, such that anyone could make up ways to process the data and do useful things with it, then maybe that would be fine. As it is the data is locked behind paywalls - if it even is directly available at all. Businesses have collected this data for free, then they keep it to themselves and they build products and sell them for nearly pure profit. It's like they're building a car without paying for the nuts and bolts - and we provide the nuts and bolts.

Instead, ultimately the data is used against you in order to get you to buy more things. It's taken from you without your explicit consent or a reasonable exchange, and then it's used against you to your further detriment.

Imagine that someone has made a false accusation about you and it becomes part of your online profile.

Within less than a day, maybe even before you aware of the claim, every major online database has marked you as being something that you are not.

Who do you call to correct it?

Will a correction fix it?

Will the false information even get deleted?

When you don't control the data, you are always vulnerable.

It's not as funny as Peace, Love and Understanding but for most of us it's all we've got left

https://www.lakeshorepublicmedia.org/npr-news/npr-news/2023-01-21/she-was-denied-entry-to-a-rockettes-show-then-the-facial-recognition-debate-ignited
This is one of many examples where privacy should really help. Another example is Google blocking account (and with it all emails, calendar, ...) of father, who sent picture of his ill daughter to doctor during pandemic.

Information is power. Telecommunication have changed the landscape of business, warfare, and how we live. It allows us to make “better” decisions for what we set out to do. Whoever holds more information, and has the chops to analyze it, controls the board. The closer that information is to individual people, the sharper it is as a weapon.

Having power too concentrated in one place or a few has led to disastrous consequences in human history. Privacy is simply a way to hold that power back, so that the most sensitive information are kept away from unknown hands.

Privacy also allows us to be ourselves, in the sense that we have different fronts of ourselves. We have sides we don’t necessarily want to show to our parents, but we show it to our friends or spouse. Not everyone has the best of relationships with everyone around them, and so there are sides we don’t want everyone to know, lest they get used as a weapon against us, either for others to exploit, or hold us ransom. If you’d like an example, imagine having an overly possessive religious parent, and you’re an atheist, but you don’t want to confront your parent because you’d like to avoid trouble. When thought in that way, privacy is a right that humans should have, and it is each person’s right to release what information they have about themselves to whoever they wish.

Oh, the contempt with which people speak about their loved ones on the internet? Privacy allows that. It's really fun to watch (and provoke). I'd lose a source of entertainment.