This is akin to minecraft duping with shulkers. Instead you just got transports.
Who cares about ore when you've got 50k cargo space which is just getting more and more. It all depends how many instances you can run. People will make their work around's to what ever exceptions you come up with. This suggestion is completely flawed and to try and argue for it is both preposterous and ignorant. People already try to multibox and this hardest line approach doesn't even stop all of them. Giving cheaters an inch leads to them destroying what is left of the game. I'm surprised this was even suggested seriously.
To TL:DR your original post it's:
"Our economy is already broken, why don't we just get rid of it/finish destroying it."
And that'd make the server a sandbox rp server instead of a semi serious rp server which it at least was and tries to be.