Home computers were only just there; the ZX Spectrum was introduced in 1982, the Commodore 64 in '83. Personal computers existed since 1975 but were way too expensive for most. There were only about 200 Apple II's (1976) sold. The original Macintosh from '84 costed $2.500, a lot of money in the eighties.
Sure, sales took off in '84 but for programmers to spawn it takes time to learn to work with computers and to program. In 1984, personal computers just started to spread among the population, from *zero*. All together, if you leave out home computer programmers, I think there were very little programmers around in 1984 compared to now and most of them were just leaving the punch card era. The remaining programmers worked with VAX alike computers that didn't use color, mice or sound.