My guess is that one solution to jaggies will be to shade boundary pixels proportionally to how much of their area is inside the triangle. E.g. a pixel that is 50% inside the triangle would be an even mix of the color values inside and outside the triangle.
For the relevant factors, I wonder if this is becoming less of an issue with higher resolution displays where the jaggies will be almost imperceptible at a regular viewing distance from the screen.
@AidanJDeAngelis -- Exactly correct!
@shadaj -- I think that's correct! If we increase the resolution (in terms of display resolution and physical pixels per inch) then this will alleviate jaggies (especially ones that are actually visible to people). The main problem with high resolution displays is the increase in overall render/rasterization time since you have so many more pixels now. Of course, other solutions to eliminating jaggies also have their own tradeoffs when it comes to compute time, memory, etc.