It is most certainly not a fact that the "Macintosh was the definitive introduction of modern personal computing to the general public."
The Apple ][ was more popular by far than the original Mac, and even so it wasn't the first definitive PC. I remember seeing a lot of Commodore PETs around when I was young... way more than Macintosh.
I was using the term "modern personal computing" to refer to a computer using what would become the standard cross-platform interface for computers: the desktop metaphor[1].
While the Apple II and the Commodore PET were undoubtedly very popular and did put computers into the hands of home users, they really were not "modern" computers. To quote the Wikipedia article I referenced above:
"The first computer to popularise the desktop metaphor, using it as a standard feature over the earlier command line interface was the Apple Macintosh in 1984. The desktop metaphor is ubiquitous in modern-day personal computing; it is found in most desktop environments of modern operating systems: Windows as well as Mac OS X, Linux, and other Unix-like systems."
The Apple ][ was more popular by far than the original Mac, and even so it wasn't the first definitive PC. I remember seeing a lot of Commodore PETs around when I was young... way more than Macintosh.