Comment 2 for bug 1600522

That is already possible. No GUI yet but you can do it by yourself.
Wingpanel will look for a default.blacklist file in the ~/.config/wingpanel.d/ directory.
 In this file there must be one indicator filename per line.
You can find the indicator file names in /usr/lib/x86_64-linux-gnu/wingpanel/
In your case for example libbluetooth.so