If you have your (encrypted) password manager file backed up to one or more otherwise unencrypted media, then remembering your master password will be enough in a pinch. But yes, for day to day password handling you’d want to have a few more memorized, e.g. the ones you’ve mentioned. As those are passwords you enter daily, it’s usually not much of a problem, especially if you use memorization techniques.
If you have your (encrypted) password manager file backed up to one or more otherwise unencrypted media, then remembering your master password will be enough in a pinch. But yes, for day to day password handling you’d want to have a few more memorized, e.g. the ones you’ve mentioned. As those are passwords you enter daily, it’s usually not much of a problem, especially if you use memorization techniques.