That's a pretty big if. If I have a standard layout with src and include directories, then I expect everything within the src directory to be included, which requires globbing. If I add a new file, then there is no reason to need to edit the CMakeLists.txt as well. Similarly, header files are explicitly listed in the source files. Having them duplicated in the CMakeLists.txt only introduces potential for error.

In my mind, anything that needs to be specified explicitly is an opportunity for error.