False dichotomy is a common tactic used to radicalize people and instigate violence.
Brian Thompson was the head executive of a corporation. He likely spent his days looking at spreadsheets and BI reports, going to meetings where he was held accountable for making a profit for the shareholders and playing golf. If he is responsible for deaths related to the 30-something percent of claims that the company he ran denied, then he is equally responsible for any lives saved by the 60-something percent of claims they approved.
I'm not mourning the guy, but I know his friends and family are. If his murder was justified, is mine justified for not feeling bad he died? Is my daughter's murder by a Palestinian justified because I pay taxes that buy bombs my government sells to Israel?
There are lots of alternatives to murder (or whatever euphemism for murder you choose to use). Murder certainly feels easier in the short term, especially when you have no connection to the guy who pulled the trigger. His life is likely ruined now as well.