Just to clarify: I wasn't using Gimp over a modem.

The ability to run graphical applications across a network may have distorted my impressions, but I am pretty sure I am remembering correctly. The modem experiences were largely things like previewing papers and preparing graphs, neither of which are terribly dependent upon interactivity. It is also worth keeping in mind that many early widget libraries were much simpler than what came later.

I used to use FrameMaker over a 28.8kbps modem and, while it wasn't fast, it wasn't impossible to use. Typing latency was reasonable, but setting up the screen was slow. Expectations were also different back then of course. Running Frame on my 486sx-33 on Windows 3.1 with 4mb RAM would have been a bear, too.