As with all estimates, figures supplied by Nomadlist, Numbeo and every other site under the sun are purely subjective. To be honest, if you look at a city in a rich country like Australia, you're going to get a huge variance in what people would consider cheap.
When it comes to my travel budget planning, I look at a bunch of sites, figure out an average, double it and budget accordingly. After a month living in the city, if it decreases, great! I have extra money for the next city I move to. If it increases, well, I've gotta tighten my belt.
Right now I'm based in Melbourne. I know that personally I could cut all corners and live for AU$1500 a month. That being said, I don't live that cheap and I know people who exist on twice that much who still complain that they aren't meeting budget.
The $1207 'living like a local' figure would probably only apply if you're willing to hang about for 12+ months. Accomodation is expensive, short-term accommodation moreso. If you're willing to live on rice and noodles (the typical student lifestyle) you could do so for $5 a day. Meals outside can range from $10-$20 per person if you want to be tight. If you live in the CBD, the public transport is free and there are plenty of parks that you can excercise in. You won't like to do that in winter though - right now with the wind chill it can drop to 5°C in the middle of the day. You don't want to jog in that with the icy rain. For the emergency fund, I always take the cost of a non-sale air ticket to my home country and double it.
In the end, when it comes to being a digital nomad, you're gonna have to figure out your own cost of living formula. Some people think cheap is living in a dorm full of stinky backpackers. Other people think cheap is living in a 1 bedroom apartment - in Australia, the difference between those two scenarios is $1000 a month.