[rcxdude]

Indeed, while I critisize the quality of the implementation, much of what they implement is necessary for or assists the development of such systems. Catkin is crap, but you need a reasonable way of assmbling multiple packages (from multiple languages) into a build, and there's not many decent options (vanilla CMake has grown a lot of relevant features now, so you could probably design a similar system with a lot less extra custom code and quirks). Their IDL is naive but you do need a standard one and the landscape was a lot bleaker when the project was started. Rosdep is mostly optional: I outright ignore it when I use ROS and just sort out installing the relevant dependencies using my package manager (If you do this you find ROS works just fine on other distros). The fact that environments are generally self contained is a huge help to development: I usually put in effort to persuade other bits of software to work in a similar manner (I try to keep each project contained to a folder: dependencies outside those available and installed by my distro's package manager should not leak outside this).