Killing is heinous act giving unparalleled suffering to others, that starts right at the moment, to many related person. Not same as one person doing nothing to reduce climate change. You are comparing apples to sky.
That firmly establishes that killing is very bad and faster. What it doesn't do is make an argument it is moral to emit large amounts of carbon that will also hurt people (but more slowly) just because other people are doing it too.
But that was the point: a person flying around the globe every week will not impact the climate significantly, even if thousands of people did the same. You're not going to achieve anything without global regulation, so trying to shame individuals is just pointless.
