Yes, you should actually pay attention during the etcupdate phase so you don't screw up your system configuration. That is supposed to be obvious.
Secondly, NetBSD is not a Linux distribution. "Rolling release" does not mean anything. Packages are separately developed from the OS. The OS's current branch is the unstable development branch. It contains live experimental changes. A "rolling release" Linux distribution tries to package the latest stable version of every package. It does not involve builds of the unstable development branch of the kernel.
We publish daily builds of the stable branch because it takes time to make releases so they don't usually contain the latest changes to the stable branch.
You would have known this if you'd read the "about" page on the NetBSD site. I suggest you look things up and read them carefully in the future so things like this don't happen and you don't need to create a million forum threads and questions on IRC.