Its more than that, its that x86 vendors know how to maintain hardware backwards compatibility, they don't throw out the entire USB subsystem every time a new phy/whatever shows up because there is a standardized mailbox interface sitting in front of the actual HW. Same with the core platform, which works out of the box using 25+ year old firmware standards that are flexible enough to support simple sensors and behaviors, like lid close notification on a laptop for example across multiple OS's. Even something as simple as the firmware interface for handing off a frame buffer to the OS isn't universally support on arm platforms because a significant fraction don't support uefi. Apple was an early uefi adopter, but whatever internal politics they have, means they tossed even that on the latest mac's.