The baseline condition is everyone is still in ICE cars -- he changed that and have altered the trajectory - the transaction cost is his own emission to raise capital and build companies. Now add in the CH4 rocket fuel - might do some counter damage to the net impact but I haven't run the calculations -- probably could do a quick one. Should be using H2 if he cared about the environment ;)
In essence, billionaires are humans like the rest of us. If we're asked to make concessions, they should have to make the same concessions.
Mind you, social morality (IE the "We should stop flying so much!" idea) not backed up by law is toothless and ignorable. Which Elon is clearly doing.
why should that be a goal of his? I mean, unless you expect that just because he's rich, that he's obliged, how his enormous amount of money is spent is not something anyone else can critisize.
I'm not presenting this as fact but the argument is clearly that Musk's net effect on the global population is positive through his career choice and life's work, and that jetting around is necessary for him to complete this life's work.