This is more common with public companies than private companies though.
Founders have their own life, honor, ethics, desires, etc. which usually help strongly keep the company on a positive track. e.g. Valve Corporation.
Valve is certainly abusing its position. It charges extremely high rents for the services it offers because of its dominance as a marketplace.
It does provide a host of services and does them well, but whether they are value for the platform fee is another question. Using those services creates lock-in and friction to port to other platforms. By providing them as part of the package, Steam has extinguished companies that used to provide those services, meaning that it’s even harder to provide the same functionality elsewhere.
SpaceX can just asked for an absurdly high price, because if they want to sell into the broader consumer market, people aren't going to pay 1000s of $ a month to watch Netflix.