When you post on reddit, instagram etc. you're giving the company your valuable data. (And it often is valuable, you put your thoughts into it and all that). Consider if you take 15 minutes to create value content, you'd get paid $5 or sth if you were doing it commercially. Now all that value is donated to big tech companies. (that's the only reason why they have value at all.)
So what's the problem with that? The problem is that reddit and others can instantaneously put your years-long effort behind a paywall. I'm not joking. Look at these:
when i want to see content on reddit (for research) or instagram (for local community) they don't allow me to see the data that users have contributed. Reddit claims that it blocks VPNs for "security reasons", meanwhile i'm using VPNs in browser's incognito mode to not be tracked. Instagram wants you to sign in sothat they amass more users and can take leverage of the network effect even more.
I can understand restricting who can post to limit bot activity, but reading must always be possible. After all, it's our data. That's exactly what happens when you give your data to big companies to "communicate with other people": your data becomes a source of income for them, at our expense.
It is also one of the first things you learn when experimenting with capacitors. You burn a few while building faulty circuits.
Right after having burned a few resistors.
The second thing we learned in electronics class was that putting a 12v cap in a mains line makes a really loud bang.
Our benches were left unplugged every day and when we came in, we were to plug them in.
This devolved into finding ways to hide caps in the outlets in each other's benches and a desire to show up very early to class.