I don't think so. Even if the main repository is organized in a linear style, it's very common for developers to make experimental branches on their own machine

I don't think so. Even if the main repository is organized in a linear style, it's very common for developers to make experimental branches on their own machines. This was inconvenient before DVCS, so you used to see things like conditional compilation or large blocks of commented-out code. People tend to work in the way best supported by their tools, and I'm convinced DVCS changed the way we work by making more things convenient. And that's not even counting large-scale truly distributed projects like Linux kernel development (the origin of git), which would be practically impossible without it.