...intermediaries follow. The more nodes, the more middlemen.
It is so cheap to complete a transaction from almost anywhere, anytime, that tiny slivers of value, built upon microcosts of transactions, can be surgically inserted into all manner of processes and products. Because each microvalue sliver is so cheap, there is economic room for multiple microvalue slivers where before there was only room for one intermediary. As transaction costs plummet to the nanopenny level, some little crumb of value can be profitably added to more and more processes.
The combinatorial mathematics of networks also boost the opportunities for intermediaries. By definition, every node on a network is a node between other nodes. The more connections there are between members in a net, the more intermediary nodes there can be. Everything in a network is intermediating something else.