> Because the readers were text-based, and it was all on my hard drive, I could consume postings at such great speed.
You didn't have to run a BBS to do this. Using an offline mail reader like Blue Wave [1] and downloading QWK files [2] allowed anyone to do it—and helped keep the lines, as downloading was (relatively) quick compared to reading 'online'.
I initially got "on" Usenet by downloading SOUP files from a local free-net [3].
[1] https://en.wikipedia.org/wiki/Blue_Wave_(mail_reader)