Once you cross the line and start threatening death because somebody did something you don’t approve of, that was perfectly legal, you have forfeited your gravitas and credibility. This is the same mentality that Earth First exhibits, while they blow up office buildings of scientists who use vivisection.
While it was legal to shoot him where they did,the methods used to get him off the game reserve most definitely were not.Plus he had a tracking collar on when shot,they removed the collar when taking his head and hide.
If I read the earlier article correctly, he baited outside the permitted hunting area and shot the elderly lion illegally. Its pretty indefensible imho.