To use a trolley problem metaphor, what they are saying is not pulling the lever is the same as allowing five people to die. If fascism is progressing and you do not stop it, you are allowing it to progress. Whether you consider that propagation comes down to your ethical framework, but from a consequentialist view it is accurate
“Orcas were given the name ‘killer whale’ by ancient sailors’ observations of groups of orcas hunting and preying on larger whale species. They called orcas ballena asesina, or ‘killer whale.’ Their Latin name, Orcinus orca, also reflects this observation of orcas feeding on large whales. Orcinus translates to ‘of the kingdom of the dead,’ and orca refers to a kind of whale.”
Source: https://us.whales.org/whales-dolphins/facts-about-orcas/
So seems like this etymology makes more sense.