If changing a process root directory is really what you want to do then yes chroot is the right tool for the job. But from a perspective of "jailing" daemons as mentioned in the article I think unveil is a better API.

I'm not sure what pieces of software populate directories and then chroot into them aside from maybe some build systems? But those likely create or bind in some /dev and /proc pieces which would be privileged operations anyway. And in such a case would containers not have surplanted chroot?