How does large-scale standardization operate under communism?

Hello. I'm having a bit of a conceptual struggle that may be the result of personal biases and/or a misunderstanding of the communist ideal. But does a decentralized power structure not make it more difficult to establish necessarily large-scale projects of society (eg. infrastructure, communication networks)? Or would a more centralized management of these concerns be considered an acceptable form of hierarchy because we could democratically relegated the logistics to experts whom exist within a classless society, so their perceived realm of authority doesn't pose a material threat to those "under" them? Or do I not understand decentralization, perhaps? Or are we not concerned with standards on a scale of, say, international highways? Because I certainly enjoy the convenience of such standards.

You folks all seem really smart and I feel intimidated asking these questions. Be kind 😅