As the experience from other users in this thread, it seems not extremely rare to have an overgrown ~/.cache/ folder.
It is the first thread about overgrown ~/.cache directory I see since I use Linux (~16 years or so). But, as I wrote above, this sometimes (rarely) happens with log files and some other directories. Checking each of them is a waste of time, if not automated, checking just one or few of them makes sense only if you are testing some app and looking for files it creates.