Inside the Little Plastic Castle

Back in the mid-90s, a lovely tool called After Dark came to the Mac. No screensaver was built in to Mac OS. MThe diligent programmers at Berkeley Systems needed to do a lot of low-level work to paint the screen with pretty images -- most famously, flying toasters.

If you're curious, a dozen of the original After Dark screen savers are available, simulated in CSS, here
https://www.bryanbraun.com/after-dark-css/

The reason those programmers were so good at directly addressing the Mac screen is they'd written a utility called inLarge, a screen enlarging system hack which permitted magnifcation of the (then tiny) Mac screen. Yet again, assistive technology users were the alpha testers.

Berkeley Systems made big money on After Dark, and reinvested some into further assistive tools for the Mac, including its first screen reader, outSpoken. But users and developer both saw the writing in the wall: the best Mac screen access software needed to be baked in at a very low level, which Apple has finally done with VoiceOver and the other AT that ships with all Mac products now.