78 kph/48 mph isn't that fast honestly, I think the biggest problem was that she was fucking wasted. If you can't keep your shit together at 50 miles an hour you probably shouldn't be driving.
This is the problem; if we don't respect any speed over 10km/hr as being fast then it's easy for us to speed. Sure doesn't feel fast when you're driving, but 50km/hr can look pretty intimidating from the ground.
The fact you're converting to mph makes me think you might not be familiar with speed laws in Australia and what the expected traffic speed is on the average street.
It's weird how they talk about grandfather here without clarifying who is he a grandfather to (I thought it was her grandfather) and how grandfather is like a title or something. I would've expected it to be reported as "killed a year old man" or something