IMHO real historical value of the 8-bit Atari is that it is the "father" of the Amiga (which offered a lot more bang-for-the-buck and technological advancements than the Macintoshes and IBM PCs of the time). Many of the Amiga's core ideas (like a separate display coprocessor which ran its own 'display list' programs) had been tested on the 8-bit Ataris already, by the same design team.
That's a pretty funny way to frame it "the real value of this historical artifact is in the fact that it was the father of this other historical artifact that I personally like/prefer".
You could just as easily say the Atari 2600, which Jay Miner also worked on, only has value in that respect, but you'd also be wrong.
Yeah the Amiga was pretty cool. But so were lots of other things.
Also the designer of the Atari SIO, Joe Decuir, also worked on the USB standards and calls the SIO the direct ancestor of USB. Too bad it's so slow. The Commodore VIC-20 and 64 (which had a similarly crippled serial interface) and Atari 8-bits all would have been even more interesting machines with a fast parallel floppy interface.
