There's plenty of worry to go around. I would like to put aside the (very understandable) fear about Google for a second because I think the GP makes a good point.
My parents used to use the open web, but have also more or less exclusively started to use Facebook to "surf the web" and get all of their information. The 2016 election was a joke, my mother would constantly tell me about all these things she'd found out about "on Facebook". She'd click these links and keep getting more and more radical misinformation. I was honestly shocked at what her Newsfeed looks like. The worst thing is she isn't an abnormality, she's fairly typical of her generation.
I'm concerned by _any_ closed platform, especially when there isn't enough competition. I realize that's descriptive of many things my employer builds as well. But please don't discount the dangers of other closed ecosystems, it's a certainly related topic. The web by _anyone_ makes it a poorer place to be and there's attackers on all sides.