Like many forms of Utopian government, this works only as long as everyone buys in - it only takes one person being selfish to bring the entire thing down. If you're planning on playing with a small group of real life friends, something like his can be feasible depending on the pack and options available. Playing like this with strangers will end in failure 99.9% of the time.
Some things to consider:
Time of play becomes a factor quite quickly, as time is the only nonrenewable resource. Any player without unlimited free time is automatically at a disadvantage since a server keeps moving even if they aren't present. Unfortunately, without somehow limiting the amount of time other players can log in (good luck building a community on that premise), nothing can be done to even that out.
Supply and demand only works if the supply is finite. If you're charging me 100 bananas for a diamond, I can simply keep my bananas and go mine my own, so long as the world is infinite. Playing in a bordered world (finite space) appears to solve this by limiting the amount of resources available, but space (and mining rights) quickly becomes an issue of it's own - again those with more free time will dominate resource acquisition, and since the world is now finite, newer or slower players find it impossible to move forward.
Other than building a community, what pushes players to actually trade rather than acquire themselves? What determines reasonable prices? Is theft an option, and what is done when it happens?
Mods like MineColonies allow players to set up their own towns, complete with alliances and enemies lists. This could be an interesting way to claim space, build communities, build pride of ownership, and set a basis for economic trade. Paired with CustomNPCs (mods would likely need to set these up as they became needed), bankers, tellers, and more become possible.
Running a world with this grandiose a plan becomes a full time job. Equal parts IT director, UN chairman, and creative God. A small group of people who you already know can help you (especially if they're close enough that you can slap one when they get out of line), but it still only takes one to bring it crashing down.
Good luck.