Monopoly isn't important. It's the control of discourse within an entire community which is key. Hell, it's not one entire community these companies control. It's hordes of communities across entire forms of online discourse for huge fractions and even the majority of populations online.
YouTube is dominant, because people make a totally free choice to use it, not because competition can’t exist.
Due to network effects, effective competition can't exist. This gives YouTube the potential to nearly absolutely control the very broad category of video discourse online.
Nothing about being dominant in a market or network effects directly implies a monopoly.
In 2019, this just seems ridiculous. This has got to change.
It’s not as though we’re dealing with Standard Oil, and if you want heat or a running vehicle you do business with them, or get bent!
It's as though we're dealing with Standard Oil, and if you want to be a full time political vlogger, you hew to YouTube's rules and politics, or get bent.