Until you can purchase a phone that is not compatible with 2g, you will always be at risk of fallback attacks. It works sort of like what you are describing in

Until you can purchase a phone that is not compatible with 2g, you will always be at risk of fallback attacks. It works sort of like what you are describing in 3g & 4g networks. So to answer your question: You are missing phones that don't work on 2G (unless there is a function to disable it in a user-unfriendly engineering menu).