if you don’t mind carrying it around with you everywhere

I doubt the target demographic for a paper password notebook is logging into their accounts everywhere, as if that’s some common ocurrence.

and hoping it doesn’t rain

Ah yes, famously, before the invention of laptops universities and schools didn’t work on every single rainy day, because paper notebooks and books are impossible to keep dry. As a matter of fact, the UK never had an educational system before the digital age for this very reason, it’s so sad.

You can’t store your passkeys or TOTP in your notebook either.

You shouldn’t store 2FA and recovery codes on your password manager. They offer the feature as a competitive selling point, but the entire point of having 2FA is avoiding single point of failures.