How would you decentralize physical infrastructure like roads, rail, power lines, sewers etc.? Someone will need to be responsible for maintenance, and you can’t exactly switch out which sewer is connected to your house in case you’re unsatisfied with whoever is running that show. I’m imagining 20 identical roads running in parallel from A to B so people can choose which one to associate with. And a hundred different internets cramming the already limited electromagnetic spectrum we have because there’s no central authority to regulate them.