At that time, if you had a PowerPC Mac, you could still run older software in Classic Mode if needed.
While many of us no longer rely on old Classic mode software, Apple gives Classic mode even less support than at the time I wrote that article.
While SheepShaver, promising emulation of Macs from the late 1990s, would seem a better solution than Basilisk – emulating Macs from the 1980s through early 1990s – I noted in that article: “I’ve been trying to make (SheepShaver) work. In it, I noted that the then-new Intel-powered Macs were unable to run older Mac software in called Classic Mode, but that there were at least a couple of ways to get around that, including Basilisk II, which emulates old 680×0 Macs, and SheepShaver, which emulates newer pre-OS X PowerPC Macs. Early in 2006, I wrote an article for Low End Mac entitled VNC, Basilisk II, and SheepShaver: 3 Ways to Run Classic on an Intel Mac.