Well, sure it's related (and MacinTalk is still builtin to modern macOS and iOS - you can use them for the system TTS voice). But DECTalk and MacinTalk weren't the only speech synthesizers available in 1999 by a long shot.

I had to chuckle about the genius of being able to program C and Lua as if typing English - I mean that's pretty much any reasonably proficient dev.