Bad information, as usual, from Tom's. The Apple IIe was the most successful, by far, and not only was released before the IIGS, it was discontinued after the IIGS.
Shakespeare was wrong about a name meaning nothing though. Apple, through their unfortunate choice of names, made an agreement with another Apple (think Beatles) so that despite the IIGS having hardware capable of stereo sound, it was mono due to their agreement. Sad, but true.
In all fairness to Apple, it has always sucked balls. A lot of youngsters have jumped on the band wagon of hating Apple lately, and that's nice and all, but keep in mind they have always sucked. The Apple II was always an overpriced, underpowered piece of crap. It lasted a long time because it got entrenched in education, but even by 1981 or so was completely obsolete, and later iterations did not change that. On top of that, they were very expensive, a nightmare to program video on, and had the miserable 6502. Their slots were bizarre in that they were not like a PC where (theoretically) any card could go into any slot. Their video was such that in some modes the color choice depended on your location on the screen. The memory mapping for video was convoluted as Hell. And did I mention it was expensive? For this crap.
To their even greater credit, they released the even more expensive, even more pathetic, Apple III. If you had problems with it, the solution from Apple technical support? Pick it up and drop it. I wish that were a lie. And it was obscenely expensive, and still had the remarkably poor 6502. Really, I'm not lying.