The way you beat an incumbent is by coming up with a thing that people want, that you do, and that your competitors can’t do.
Not won’t. Can’t.
How did Apple beat Microsoft? Not by making a better desktop OS. They did it by shifting the goalposts. By creating a whole new field of competition where Microsoft’s massive entrenched advantage didn’t exist: mobile. How did Microsoft beat Digital and the mainframe pushers? By inventing the idea that every desktop should have a real computer on it, not a terminal.
How do you beat Google and Facebook? By inventing a thing that they can’t compete against. By making privacy your core goal. Because companies who have built their whole business model on monetising your personal information cannot compete against that. They’d have to give up on everything that they are, which they can’t do. Facebook altering itself to ensure privacy for its users… wouldn’t exist. Can’t exist. That’s how you win.