Thanks to my years as a cyber crime investigator, I get questions from authors all the time about social media. Which platforms are safe? Should people stop using <insert-platform-here>? Which do I use myself? 
Let’s go over each question. Are social networks safe? That depends on your definition. If “safe” means “secure,” as in “not hackable,” well, bear in mind that technology is designed, implemented, and maintained by humans. Humans make mistakes. There are steps you can take as a user, like applying 2-factor authentication (“2FA”) whenever possible. But, ultimately, it’s best to acknowledge that your data is out of your hands/control the minute you put it online.
If “safe” means “private,” that cliche, “if the product is free, you’re the product,” applies. Every social network I can think of is, essentially, an advertising company. They didn’t build their apps or platforms out of the kindness of their hearts, they exist to make money. Online/mobile ads are lucrative. The more the provider knows about you, the more targeted they can make ads in the hope that you’ll click on them. It’s called “pay-per-view” and “pay-per-click.” Views generate a nominal return, clicks earn more because the advertisers know they’ve gotten your attention. That’s why the platforms collect as much information about us as they can. If you want to see exactly what Facebook, Twitter, or other platforms know about you, they all have ways for users to download your own account activity histories. You can usually find the method to access these histories under you account settings. 
If you’re concerned about data privacy, and you live in a European Union country, you have rights under a law known as “General Data Protection Regulation” aka GDPR. On January 1, 2020, California’s privacy law that closely mirrors GDPR goes into full force and effect for citizens of that state. These laws require “data processors” – including social networks – to adhere to standards of care and provide a “right to be forgotten” mechanism, meaning a way to delete your account. What these laws provide are guidance for handling user data, and financial consequences for failures (breaches). And they will all fail at some point. Remember what I said about humans?
Should you delete your account, now that we’re learning about how our data is used? It depends on your reason for caring. I’m not suggesting we shouldn’t care about privacy. However, it’s a tricky subject. Basically, if you use a computer or mobile device, you’re giving up a measure of anonymity from the get-go. Everything from the type of operating system you use to the way you type can be detected and stored by websites, online retailers, social networks, and others.
I’m not planning to delete my Facebook account. There’s not really a point. My data is already out there. That said, I have slowed down my usage. But the reason isn’t political or privacy-related. I wandered off long before anyone heard of Cambridge Analytica. I have limited time and energy, and there are a lot of choices. I found myself gravitating more often to Twitter. I like the immediacy and the simplicity of its reach. It wasn’t really a conscious decision, it’s just where I’ve ended up spending most of my social networking time. My advice is to find what works for you, where and how you’re most comfortable engaging with readers, writers, agents, editors, or whomever. Get familiar with your chosen social network’s privacy and security settings and, again, whenever possible, enable 2FA to protect your account. The safest bet when interacting with others on any social network is a maxim popular in cyber security circles, trust but verify. Actually, forget the “trust” part. Verify before believing. And remember the Golden Rule still applies, online as well as in real life.
