https://www.ftc.gov/news-events/news/press-releases/2023/09/ftc-sues-amazon-illegally-maintaining-monopoly-power
The Federal Trade Commission and 17 state attorneys general today sued Amazon.com, Inc.
forgive me if I'm wrong, but from what I have heard about video hosting is that it's actually very expensive and YouTube doesn't really make much profit in comparison to other social media
You are correct. YouTube is tricky for several reasons, and hard to prosecute because the true monopoly is discovery (because everyone uses it).
Content can be consumed anywhere, you can follow some niche creator on Patreon, but YouTube is realistically the only place you'll discover them.
YouTube chooses to demonetize and outright ban perfectly legal and normal content that happens to disagree with their politics. On it's face this is okay, they're a private company after all, but the insidious thing is that entire subjects may as will not exist for you know because YouTube bans them.