NewOldGuard [he/him, they/them]

This is not true. You may be thinking of the Secure Enclave, which Apple processors have had for a while and acts as a dedicated piece of silicon to protect encryption keys. But pixels have this too, idk about phones with Qualcomm or exynos SOCs but they likely have something similar. Either way it has no impact on battery life and all major smartphones have been capable of encryption for many years