Well, I'll tell you why I'm on Facebook.
1. There is no other site that connects me to the people I personally know on the web. Friends in the US, the UK, Spain, South Africa, and all the other countries I've lived are there. I have maybe 120 people on my FB account, and that's it. It's easy for me to keep in touch with everybody that way. These are my friends - my real friends. I've lived ina lot of countries.
2. I don't care what information Facebook has about me. It is completley and utterly useless. I am not an American citizen. I am a dual South African/German citizen.
3. I am a minimalist. I own my laptop, a camera, a phone, and all my bedding, kitchenware, clothes, and everything else (including things like a small kettle, small pot, small vaccum cleaner, fit into those five suitcases. I don't need anything else.
4. I don't own a TV and I haven't watched TV for 15 years. I don't own a car. I don't have any accounts. I live strictly on a cash basis. I don't want things. I am completely blind to advertising. Even when I play a game on my phone, the minute there is an ad, I put the phone down and I won't watch. I refuse to watch advertisements
5.All the posts on my fb page are ones I enjoy. We all tend to be progressives, liberals, etc. But I'm more interested in climate change than anything else. As we're all old (I'm 70) and as most of us are geeks and pretty sophisticated when it comes to tech, we don't get caught up in things like fake news.
6.I cannot remember seen any junk on my page for a very long time.
My point is that fb is what you make it. If people are that wrapped up in what people they don't know are doing, one has to ask why.