So; what exactly are Apple's big, selfless contributions? XNU is Source Availible but unusable without buying proprietary Apple hardware. iBoot is mysterious and has to be reverse-engineered to use it like UEFI. Open standards like Vulkan are ignored for political reasons, CUPS is basically derelict, WebKit killed KHTML because sharing was too hard, and APFS and Metal are still both undocumented despite promised transparency. CoreML is proprietary but can't compete with CUDA, iPads can't use QEMU despite supporting it in-hardware, all the Apple Silicon DeviceTree code is private, competing runtimes like Corellium get sued and security researchers get ignored. Swift, as an offering to the Open Source community, is a punch line at the end of a 20 year long gag.
Apple does genuinely nothing to advance the wellbeing of common computing for mankind. Apple leaves behind no charitable contributions to anything that does not ensure their absolute preservation as a business. Combined with the proven anticompetitive damages that the App Store incurs on the burgeoning mobile market, they are unequivocally a net-negative force and aren't hated enough for their parasitic influence on global software production.