It happened when Apple moved to OS X, but the user base was much smaller so the complaints were less.
I'm sorry, this is just not the case, Apple did a REALLY good job with the classic environment in Mac OS X and most of these complaints were known, but it was OK, because everybody could see how much better Mac OS X was than classic.
1.) Old antivirus programs weren't a big deal because there weren't any. Microsoft has an interface that notifies XP when an antiVirus is being installed, it might be possible to prevent an antivirus from being installed by claiming there's one installed already. Or maybe, MS just doesn't care because it's a VM anyhow, and they just have a new copy somewhere else on the computer.
2.) This was a big problem with printers in the OS X switch over. Epson in particular lost a lot of repeat customers because they refused to update some of their USB printers to support Mac OS X. One solution, was to install the printer driver in Classic and print only from there. But anything you wanted to print from Mac OS X had to be compatible with the old program.
3.) 3D games? I'm sorry, they just worked. Really. No Joke. They were slightly slower, maybe 2-3 FPS slower, but nothing major. It was great, I could play all my old games without having to reboot into the classic environment. A few games I had were upgraded to be able to be played on OS X, and those games got a huge speed boost when they did. On OS 9, they'd get somewhere in the 30FPS range, then 27-28 when played on classic, then, when they were upgraded, they got somewhere in the 35-40FPS range.
The other thing that probably makes my memories a lot rosier is that OS 9 was so outdated and crashy by the time OS X came out, we were very glad to switch to something that didn't crash.