And it's no more easy to start any of those on your own than it is to start your own ISP. Sure the barrier to entry to make your own website at some random domain is pretty low, but that's more akin to setting up a wireless router to provide internet to your roommates and calling it an ISP than it is to making something with any sort of significant penetration, load handling capability, and financial sustainability.
The argument of "ISP's choice is very limited in many areas, so it's different" seems rather weak to me. You can just use a cell carrier, or satellite, or even dial-up. If that sounds like "you can just start your own social media platform, your own website, your own payment processor, your own registrar, or just be accessible through an IP address, or tor etc." it should. All those options suck.
E.g., your ISP is likely not the only option, just the only decent one.