I mean that's C++ development in general.. even among package managers you had to deal with conan, vcpkg, hunter, and a dozen more ..

And then add to that the complexities of build systems and cross platform, cross complication headaches...

That being said, for most of kde end user applications, fixing quick little bugs is usually just installing the devel packages from your distro, git cloning the application, a couple of compile debug cycles and then sending the patch on their gitlab..