It's one thing for the Linux kernel to still support 15+ year-old hardware (the Athlon XP was already pretty old by 2008). It's a very different thing for a ful

It's one thing for the Linux kernel to still support 15+ year-old hardware (the Athlon XP was already pretty old by 2008). It's a very different thing for a full desktop OS to still support it in a feature-complete way. Historically, Apple seems to prefer to drop support for old hardware rather than maintain a long list of caveats about which features cannot run on older machines. Throughout the Intel Mac era, Apple was clearly trying to raise the bar for baseline GPU performance to ensure the graphical effects really would run "perfectly fine" as you put it, though they were stymied by some of Intel's anti-competitive behavior. Their decision to drop support for the 32-bit kernel and firmware was quite reasonable, though the later decision to drop support for 32-bit applications was more of a problem for users.