Just about every application on Apple 2e relied on keypresses being shown on the screen. Modern devices and operating systems are displaying 'windows', streaming 3d graphics etc. and running a myriad of other services at the same time.
Even in a mostly passive app like a video player, it sucks if the play/pause button has a long-delayed effect. The tendency is to press the button over and over and feel correctly that we have lost control of the app.
Secondly, not every PC in 1999 was capable of even running QIII (let alone at a high frame rate).
During the days of true low-latency gaming, actual game frame rates were in the low 20s and even consoles rarely achieved 50 or 60 fps.
If a game was playable at 20s of fps, I don't think it deserves a title of low-latency gaming.