The more references to 'green' and 'eco' a tech startup has in their proposal, the more likely it is to be smoke and mirrors. Not because green and ecological aren't laudable, but rather because they are. Proudly announcing such laudable goals and motivations is a cheap and easy way to build up wishful thinking and suspension of disbelief. It also makes people who see your bullshit hesitant to call you out, for fear of 'diluting the message.'
Supersonic freight is not economical. You can get air freight from any airport to any other airport in the world in max. 24 hours flight time. Customs clearance on either end alone takes longer than that.