What resource is scarce? We can’t give everyone an iPhone or a McMansion, but we could probably feed everyone.
1) Most people would not be content with just the basics. We like shiny new stuff like iPhones or fancy clothes or nice food
2) Even if there was no scarcity of anything, our distribution systems (Globally) are pretty poor. I doubt we could flip a switch and begin distributing resources to everywhere in the world that needs them.