You could fit an entire modern OS in that space, together with all the drivers, a web browser, an office suite, graphics editor, an IDE and a compatibility layer for running Windows applications.
Yup, my Linux install is a bit over 10GB, which honestly surprises me and means I probably should clean stuff up, because usually my Linux base install is around 8GB. After a quick look, I have several old versions of compilers and runtimes that can be cleaned up w/o breaking anything.
I can't imagine thinking that an 8GB cache is fine, and that's nothing compared to the size of the rest of the OS...