>> but when it came down to actually "using" the systems, folks weren't typically shouting at their machines to go faster.

Did you ever download or upload files?

>> scrolling simple prompts, simple menus, text messages are all fine at 1200 baud.

Yes, on a 80 column text screen, there was only so much you could see at a time. People who have only seen web pages with inline images at high resolution that load instantly would probably see 1200 baud as slow.