There it goes! One more thing to do precisely and not only at dedicated time but continuously on top of all other things to do precisely already inherently around completing a task. Everyone all the time think about the state of changelog communication in addition, and do it well, phrase it for changelog purposes, format it for that as well. While working on changelog on the end will need additional work still.
In some simple situation it may have merit though, I admit. Seems like additional trouble (both workload and source of mistakes) in a medium to large team.
Except if the developers are well programmed robots themselves, of course, those do not fail (or easy to throw out and replace if they do).