One can opt to save the keys on a personal computer wallet. The keys will be retrieved only by using a password.
Second, one can also prefer to print the keys on paper and keeping them in a bank locker.
you are right, but the matter is the place that can be okay. And depending how scure is your computer, if is computer everyone touches is not good to store or save your private keys in your computer. People being recommending saving offline as you said about paper storage of private key, but only disadvantages for paper storage of keys is house burnt, if mistakenly house burn by electrical installation or appliances, your private keys cant be retrieved