In this case "decentralization" means drastically less overhead in terms of simply taking your dirty clothes to the other room instead of dealing with the hassl

In this case "decentralization" means drastically less overhead in terms of simply taking your dirty clothes to the other room instead of dealing with the hassle of traveling somewhere with it and potentially paying money per load and/or dealing with other tenants that might be using all the machines. People in the US don't use communal laundry because they want to, they use it because they (most likely) have to because they are in a large urban center or can't afford the appliance. This is basically the reverse of the internet centralization/decentralization example, where centralized services on the internet are much easier to use than their decentralized counterparts.