I would say centralised is easier but usually worse instead of better. Most people use some centralised middleman out of convenience. Decentralisation is universally better IMO because there is no single point of failure and no choke point to nickel-and-dime users to death.

> some teams can't continue to work even though git is decentralized.

I think you mean some teams won't continue to work because they don't know how to use git. If the de facto center goes down, a team is still able to use git to share changes with each other.

And IPv4/6 is decentralised, DNS makes it convenient for regular people to use. I would say DNS is decentralised as well, just the allocation of domain names comes from a few sources.