Don't they ? It might not be really obvious, but take a Walled garden platform like iOS for example. Already third party developers can't build their own browse

Don't they ? It might not be really obvious, but take a Walled garden platform like iOS for example. Already third party developers can't build their own browsers and all are efectively a skin over the Safari web engine. What this means is that iOS is effectively one lawsuit (ore even major bribe) away from RIAA or other similar unscrupulous group dictating what sites you can access and what you do with the browser. And you can't just sideload another browser due to the walled garden! And it's not just iOS as there are unfortunately many Walled garden platforms these days - smart TVs, game consoles, browser extensions for some browsers, etc. Even Android limits what you can do with a ROM that is not rooted - and some high profile apps will refuse to run on a rooted one!