If you start following tags or certain people you'll visit the dusty corners, but the FYP is remarkably good at filtering out incendiary stuff, at least in my experience. I get basically all good vibes, nothing like Twitter/Reddit, and I'm never angry or high strung after watching TikTok.
You're right about turning off your brain. But not everyone wants that thing turned off
If I see a random blog with text, I have no idea of anything regarding it without first reading (or skimming) it. But within one second of watching a YouTube video, for example, I can know a lot about the video - how professional it is, the "genre" it's in (e.g. BookTube vs Fitness), etc.
Plus, jumping around a video of an explanation on how to do something with the computer is actually fairly easy. It's easy to jump past the "here's how to install the app" part and straight to the "here's someone with a code editor open editing the thing I care about".