My interest in CLI is for use in automated continuous integration testing. For this purpose, it makes sense to always test against the newest release versions of the library dependencies.
However what would concern me is if the core Arduino developers are spending time on a niche product at the expense of work that would benefit the 99.99%.
I am concerned that the command-line-system that I use every day will be abandoned in the future in favour of a more complex system that offers no advantages for me.
It is true that we already had a working IDE and that this move of extracting all the non-GUI functionality from the IDE's Java code and moving it to dedicated external tools is likely driven by the Arduino Web Editor project, but it's really the right thing to do from a long term perspective.