The internet is already the global mesh network. It turns out one individual contributes nothing, compared to a 1000km 10000Gbps fiber link that costs millions of dollars to lay. But nobody is actually stopping you from getting ports at two DCs or IXes, somehow getting them connected to each other, then charging people to carry traffic between them. I got a price quote for about $800/month to carry 10Gbps 650km in Europe, so that's what you could potentially earn.