Software for poorly isolating software on a desktop without a viable approach to containing arbitrary desktop software with a case-by-case consent model for access is not comparable to a mandatory app sandbox with yearly backwards incompatible privacy/security improvements. The whole app ecosystem has to support it and adapt to gradually improving privacy and security. Desktop applications are not written to work that way and do not have to adopt technologies people come up with catch up to Android versions from 15 years ago.

Traditional desktop Linux distributions have atrocious privacy and security. The security record is very poor. The security record does speak for itself in that it has been a disaster. iOS and AOSP have massively improved upon the legacy Unix security model. A traditional desktop OS cannot properly protect users from applications, remote attacks or physical attacks such as extracting data from an After First Unlock state device. It's not only the software that's very lacking but also the hardware and firmware for the Windows and desktop Linux ecosystem. macOS has a made a lot of progress for the hardware, firmware, hardware-based security within the OS and a gradual move towards a mandatory app sandbox and other protections which have not happened in the Windows or desktop Linux world.

AOSP has an increasingly usable desktop mode and supports running traditional desktop Linux within hardware accelerated virtual machines. It's not fully ready as a desktop replacement yet but it's getting there. Android will be shipped on many laptops in the future as a replacement for ChromeOS. The desktop mode is going to be the main way it functions on those so it's going to get much better. GrapheneOS has all of this functionality. Many people are trying out the latest Android 17 desktop mode on GrapheneOS and were already using the earlier experimental mode. Major improvements to that are coming. Many people are quite happy with this even if you don't want it.