I've used 1980s hardware. In the 80s. And used UNIX and HP/Sun/SGI/etc hardware since the 90s. Not only it was no "truly responsive", nothing opened in a "single frame" (talking about X Windows). Took way longer then 1-2 seconds to open a browser on a blank page for example, and for many programs you saw them slowly drawing.
And I did. And it did. Like, Amiga, even 500 models.
I do not doubt X was horrible from that pov. I remember R5. This is not that I meant.
edit: there were no web browsers back then. the effin "folder browser" opens slower on my xfce4 than the same in an a1200 emulator in a window next to it. this is sad.
Not only it takes a second just to redraw a moved window (with mid-way frames and flashing in between), opening a tiny program is slow and shows the "zzz" busy indicator.
