Very true, but I haven't seen anyone cycle over the atlantic yet. People also don't take ships over the Atlantic either, not for holidays, unless the journey is a cruise.
In order to replace long haul flights, there needs to be a fast and fuel efficient way of getting around the world and, in the modern world, simply saying "don't fly" is not going to work. Our world is too integrated. Granted don't fly gratuitously is more possible.
There is a reason why ships stopped sailing and started using engines. It comes down to the English phrase "When your ship comes in". Quite literally, people traded via ship and around the world exchanging modern manufactured goods for furs of exponentially more value. Or gems etc.
But when your "ship" takes 3-6 months to return with your profits, if it returns at all (not all sailing ships did), then you could make your profit.
Today, in a connected and fast moving world, going back to sail is never really going to work.
If we want to have clean green transportation, then we need to move forward to a technological clean green transportation.
I put out there the idea of a submerged floating tunnel.
https://en.wikipedia.org/wiki/Submerged_floating_tunnelOn top of that I added the vactrain
https://en.wikipedia.org/wiki/Vactrain#:~:text=A%20vactrain%20(or%20vacuum%20tube,partly%20evacuated%20tubes%20or%20tunnels.
Which also uses maglev.
The problem I see is the only maglev train built has an induction track, which may be viable for a few hundred miles but I can't see it being possible for thousands of miles.
Norway has finally decided to go with a floating tunnel. Nobody has yet decided to go with a vactrain, but the hyperloop is still out there as a possible.
If we want to get out of air and sea surface transport and remove the emissions of both, we're going to have to make some hard decisions and follow them through.
