Can you detail some of the rock solid solutions in 2008 for the problems addressed? For example, building multiple C++ packages from source. Google's Bazel wasn't open sourced until 2015, so solutions were still appearing long after 2008.
Actually I don't really understand the problem, what do you mean with "C++ packages"? AFAIK C++ still has no concept of packages (although this has been proposed), so you probably mean how to build C++ based software that is located in different directories or how to do hierarchical builds in general?
That is supported by most build systems, plain old make can do it, CMake can do it, scons can do it, the list goes on and it is actually not something special in software development. It's not like we were unable to build software consisting of multiple "packages" before catkin or bazel.
I'm not saying that these existing solutions are perfect and the problem in general (dependency hell) is pretty hard to tackle. It's just that I don't see how catkin and the workspace concept help here.
Btw. did you know that catkin_make, successor of rosmake, is already old-school?
It's now "catkin build" - oh no wait, that's again uncool if you go with ROS2, there we have our meta-meta-build system "ament".
#edit: I kid you not, it's now apparently "colcon".
catkin_make and catkin-tools (where "catkin build" comes from) both use catkin. They're just different CLI tools, and for the most part compatible, and have been fairly stable for about four years now. How many build tools have come out for JS over that period?
Workspaces are actually super useful. They're a similar idea to virtualenv and conda environments. If you don't find those useful I don't know what to tell you.
Since ROS2 is essentially a fresh restart I'm not surprised there's some churn. I think most people expect it to be fairly unstable for a while.
I've been working with ROS since nearly the beginning (as well as other middleware solutions) and I definitely see a lot of its flaws, but understand the rationale for a lot of the decisions. It's like C or C++, a 'worse-is-better' solution that's overall pretty decent, specially considering it's open source.
