Did some of the preceding posters even read the linked article?!?!
The guy is suing because he feels the airline should have easily spotted that he was not fit to fly (appearance, demeanour, disorientation, missed pre-flight briefing all allegedly indicating that something was wrong). He is not arguing that he was fit to fly.
It is irrelevant how many people it took to hold him down. As to the compensation... If the airline is shown to have been negligent by allowing him to fly that day... he and all others on board may be rightly entitled.
If the pilot has good evidence, this will be interesting to watch.