Yes, well maintained car can and do go a very long way. The thing is when buying used at best you have a service history to go on. You don't know how or where the car was driven between services. So that is why your only measure to go by is distance. Obviously that implies a car could have been abused and then traded in with a lower mileage than another which wish handles gently over a longer distance. Yet you don't always know that.
Yesterday I had an enjoyable drive to Sutherland in an 8 year old car and the odo is close to 66,000km. I regularly see similar cars for sale at the same price I paid but having done close to 150,000km.
No brainer if you ask me.
There are many ways to tell if the car was abused. By the driver, the type car, exhaust smoke, parts replaced in the full service history, etc.
Many sensible people would stay away from an 8 year old car with 66,000km, because it implies much stop-start/short distance/city driving. Long distance is much better for a car. There could be teething problems at such a low mileage which, if the car had been closer to 100,000km under its assumed 5 year/100,000km plan, would have been claimed for.
But the dealers and car salesmen do love abusing the myth of low mileage. Remember, the less their clientele know, the more money they make. Perpetuating the low mileage myth merely keeps said clientele ignorant, which then perpetuates the low mileage myth further.
Distance will always, incorrectly, remain the greatest measure. Until people start doing their homework. Which is what we're here to help with with our knowledge, instead of aiding the spread of mistruths... Why would you, when you yourself have/bought higher mileage cars?