Why GPG does not ask me for password when using a private key?

I have used GPG on Windows and Linux and they always ask me for password to unlock a private key. Sometimes they cache a password inside the agent, but after each restart I have to enter a password at least once.

This is not a case on my MacBook. Whenever I do sign or decrypt, it never asks me for a password to unlock the prate key! It only asks for the password when I am importing or exporting a private key.

It seems like my private keys are stored unprotected within the OS, which makes me unnervous.

Does anyone know what is going on here?

macOS Big Sur 11.6 running gpg (GnuPG/MacGPG2) 2.2.27

If you selected Save in Keychain when entering your password to GPG, it was saved in your login keychain.

This keychain is automatically unlocked when you enter your password to log in or unlock from sleep, and you can manually lock it from Keychain Access (or its menu bar item) and/or remove the item from keychain to enter it every time.