A PC-XT with a modem and Telix is a perfectly cromulent substitute for a vt100! Some of my first internet experiences were on a similar machine, and a Toshiba laptop with a monochrome, text-only LCD and no hard drive. 1200 baud, though. Dialing up the local university's terminal server from whence one could telnet to anywhere...I used it mainly to connect to LPMuds.
Even through the late 90s, my wife's main internet access was through a local freenet like you describe.