I was wondering how this speed compared to a telegraph operator sending Morse Code. Googling about, words per minute, based on the standard five characters per word plus spaces and punctuation, works out to about bps * 1.2.
So 20 bps is about 24 words per minute. Compare this to a skilled telegraph operator, who can manage 40 wpm.
So yeah, it's slow, BUT for keylogging it couldn't keep up only if users typed constantly
, which they don't. Plenty of time in between to do some catch up.