What is Anti-Aliasing? simple FXAA would fix those jaggies up, the game couldn't be too hard on console video to not have it
FXAA = Fast Appropriate AntiAliasing. You just described via your solution, what the problem was.
Aliasing = graphics looking weird. Here's an example:
Say you're looking at a brick wall in a video.
As you start to move away from the brick wall, eventually the bricks will generate a pattern because their own pattern will coincide with the pixel resolution in the videocamera.
That's aliasing.
You can achieve a similar effect if you've ever looked at things through a mosquito mesh or a dithered bus window. Happens even more if you tilt your head, where the pattern will appear to dance.
In order to stop these effects in games, where the resolution used to be quite low (N64), the game would 'smooth' the graphics. You'd end up with somewhat blurred edges in your polygon models, but the game wouldn't look so pixelated and 'aliased'. This came to be known as 'anti-aliasing.
It is related to the 'jaggies' in games because at certain angles, the jaggies become more pronounced. If you apply an anti-aliasing effect to the entire screen, it smooths out everything, but you also lose some detail.
It's why N64 games looked slightly washed out (native hardware anti-aliasing) while Playstation games looked aliased and pixelated (take a look at old PS1 games that used polygon models).
There's some processing overhead involved in any kinda of AA technique, and the bigger the resolution, the more work has to be done to smooth it out. Your graphics card probably has a slider bar in its settings where you can control how much anti-aliasing is done in your games, with no anti-aliasing generating a crisper, albeit pixelated image, and the full anti-aliasing generating a smooth but slightly blurry image.
Jaggies are related because they're resolution-based.
Say you draw a diagonal line in a paint program. If your line isn't a perfect 45-degree diagonal, it's gonna generate tiny 'jaggies' as it slopes upwards. These 'jaggies' become less noticeable the higher your resolution is. However, if certain color combinations and graphic sampling techniques aren't applied, it can result in these jaggies still showing up even with all the techniques in place (if they're not done intelligently).
When the jaggies are apparent enough that they break the immersion in a 1080p or 720p game, it tends to become problematic and it's a sign of sloppy graphics processing methods, etc.