One of the root causes for centralization is that we lost the ability to make our devices talk directly to each other. Before the Internet, people could contact each other directly by just making phone calls, and the phone network was neutral, so any phone or any network could call any other (even internationally) provided they pay the fee. Same with SMS and MMS. With the early Internet, every computer had an IP addr…
the more you learn about SS7 and the traditional phone network the worse it looks. it's actually held together with the metaphorical equivalent of duct tape and string, and is highly centralized...