Yet for some reason, people still use Steam as a “gotcha” to justify why Apple’s terms are fair.

But as you’ve hinted at, Steam is very different from the iOS App Store because it is competing organically with other app stores on Windows. Steam does not control Windows or the hardware, so it cannot “force” itself to be the only option to download games on Windows.

And even when it does have full control over the platform and HW (Steam Deck), it’s just a light wrapper around a standard Linux distro (Arch).