Turn off two step verification

The older 2 step verification can be turned off. The instructions are here -> Two-step verification for Apple ID - Apple Support (note that 2 step verification uses 4 digit codes sent by SMS text).

However the current 2 factor authentication cannot be. It is required for many Apple online services used with an AppleID. See -> Two-factor authentication for Apple ID - Apple Support (note that 2FA uses 6 digit codes sent, by default, as encrypted iCloud notifications).

Apple requires it. AppleID 2FA has nothing to do with your physical devices and their security. It has to do with your AppleID and using it to login to and use Apple online services (iCloud, iMessage, FaceTime, the App, Book or music stores, Apple Pay, etc). Apple requires the added security of 2FA to your AppleID for use of and access to those online services.

Since those Apple services are hosted on Appple hardware, and Apple is responsible for storing your personal data, they like any other online services company have the right to set the requirements for remote login access to those services. For Apple, that is done via the Appleid login ID.