If you want to edit text files, do some spreadsheets, maybe send and receive messages, an IBM PC will do the job. Just be sure to have a modem, Qmodem, and the numbers of your favorite BBSs.
With an IBM PC, MS-DOS 6.21, Turbo Pascal 7, Qmodem, Edwin, pkZIP, and a stack of floppies for backup, and you could stay in business for a very, very long time, if you don't expect more each year.
Look at what people are managing to fit into a boot sector... BASIC, Games, Demos, etc. We're wasting most of the bounty of Moore's law. Not all of it, of course...the ability to stream video from anywhere on the planet for $50/month is something I only dreamed of back in the 1990s.
We have amazing computers now, but those old machines, like the Model T, can still do their original task, if you invest the time and effort to maintain them.