"..getting away with murder.."? Hardly. Collectively, airlines barely make a profit. In the short term, nothing good ever comes from resisting force from authorities. If the doctor got up and walked off the aircraft, nothing would be heard. No harm done. His patients would have been looked after sooner or later.
In the long term, the doctor, (passenger), will benefit greatly from the lawsuit, and future passengers may benefit from legislation and/or policy changes.