The fundamental advantage of vi is that it doesn't have a mouse. If you were born with three arms you can go for sam or something.
But of course he was wrong about 1991-2026:
The days of non-raster stuff are numbered, though sheer momentum will carry it to the end of the decade.
And about AT&T as the same year (1984) they introduced BLIT terminal:
The fundamental tension in UNIX that I think AT&T doesn't understand is that everyone is going to have a bitmap.