That was true for a year or so. It didn't take too long for the PowerPC in emulation to run faster than the fastest native 680x0. Daystar, for one, offered 68060 upgrades for Macs, but they never really caught on; developers had moved on to PPC, and the need for fast 680x0-native execution was a shrinking niche.
There was also a software emulator for x86 platforms running DOS/Windows and Linux called Executor, from ARDI. ARDI reversed engineering the Mac ROM and build a 68000 cpu emulator, enabling Executor run many (but not all) Macintosh software, from system 5 to system 7 with good speed.
I think Executor evolved into SheepShaver, a 680x0/PPC emulator for Mac on Mac. Since Apple didn't port Classic over to Intel (and dropped it from 10.5), it's the best way out there to run really old Mac code. I fire it up occasionally for old games when I'm feeling nostalgic.
One of my managers was nor enamored of my new Mac Plus when I fired it up at work. He said, What can that do that I can’t do. I think it was early 86.