ATC wants you to maintain that speed for spacing and to maximise their arrival/departure rate. If you can do it, DO IT. If you cant, DONT DO IT.
Most competent operators are more than capable of politely saying "Unable LAHSO" to ATC on a daily basis at many of the major airports in the U.S. So why was it so hard with speeds on final approach for the Asiana crew?
The moment they heard the infamous "Maintain 180 knots to 5DME" they no doubt began sweating. I wouldnt be surprised if these guys even knew that they could "dare" tell ATC "Unable"
Blind adherence to instructions as usual in Korea. What if ATC asked them for 200kts to 5DME? No doubt they would have tried.
Flying 101?