Psh - I knew I'd get at least that reaction.
You know what's even easier than cutting lines or even squaring off turns? NOT HITTING ANOTHER CAR
The ability to drive skillfully, with purpose, and safely, doesn't require perfect adhesion to pavement markings. Because smart driving involves adapting to the situation when necessary, whether due to pedestrians, cars, weather, illumination, visibility in general, etc. If cutting a corner means hitting another car - that's a very easy thing to correct for, by not cutting the corner into the other driver's path. It's brilliantly simple for anyone remotely paying attention.
People who struggle with anticipation of future location of bodies in motion, on the other hand, probably just shouldn't be driving. Because that's all this takes. That, and a respect for the road and the rolling 2-ton death machine they are driving.
Otherwise when it's obviously safe to do so, cutting corners will mean more efficient turns at higher speed which can be necessary to safely execute some turns based on traffic. Can also be more efficient for the tires to use all of the available pavement for turns even when it's low speed. It's just another thing that can be done that doesn't reflect anything on a driver's awareness. It can cause issues when done by unsafe drivers in the wrong situations, but frankly rolling in a straight line can trip up those same drivers due to a lack of critical skill and/or awareness, or otherwise their overall alertness and wakefulness. Driving in general should come with a particular attitude while piloting said rolling death machines, but that's not respected by many drivers. Many just aren't cut out to drive and licensing standards should be far more difficult.