There are two OS platforms for desktop/laptop usage: MacOS Windows
These both contain ways to run arbitrary compiled code from an arbitrary source -- like a computer should. Losing this feature of our smartphones should have everyone concerned.
And they're both working towards taking that away.
For now we have Linux as a 3rd option, but that only exists so long as there's hardware available that'll let you run it. Can easily imagine a near-future where you can only get 'Windows hardware' or 'Apple hardware' and nothing modern that'll boot a 3rd-party OS.
For precedent, Microsoft locked down their own ARM hardware to Windows.