The word "internet" doesn't appear in Neuromancer because in most respects it hadn't been invented yet.
While DoD declared TCP/IP the future standard for military networking in 1982, IBM, DEC, and AT&T only adopted TCP/IP in 1984, a couple of months before Neuromancer went on sale. Gibson notoriously wrote it on a manual typewriter circa 1982-83. (It took a year from acceptance to put a novel manuscript into production back then: very often, it still does.)
ARPAnet existed in 1982, Public BBSs had been a thing for a while. But the publicly accessible global information network with visual representations of corporate presence? That was all in his imagination.
Those three come quickly to mind that were certainly trying very hard to be the " publicly accessible global information network with visual representations of corporate presence" you are speaking of.
While the others did, Gibson seemed not to have been aware of them, and he didn't even own a computer at the time.
You can tell his vision of cyberspace came entirely from his imagination because it doesn't even remotely resemble any actual computer systems of the day.
While DoD declared TCP/IP the future standard for military networking in 1982, IBM, DEC, and AT&T only adopted TCP/IP in 1984, a couple of months before Neuromancer went on sale. Gibson notoriously wrote it on a manual typewriter circa 1982-83. (It took a year from acceptance to put a novel manuscript into production back then: very often, it still does.)
ARPAnet existed in 1982, Public BBSs had been a thing for a while. But the publicly accessible global information network with visual representations of corporate presence? That was all in his imagination.