Because some users experienced accidential grows like OP had 160 Gbyte. So general advice for linux users can be stated as: Check your ~/.cache every now and then
Critical systems/servers shall better be monitored as you suggest.
I don’t get your point. Why should somebody do this every day?
As the experience from other users in this thread, it seems not extremely rare to have an overgrown ~/.cache/ folder. So checking it from time to time is a good advice. If we all do this for a time, and create bug tickets for software which is not cleaning up. Then this problem will hopefully go away with future software releases.