T2 chips retain sensitive data in their secure enclave. Before selling or otherwise disposing of a Mac with a T2 chip, clear all sensitive data from the secure enclave by starting up in Recovery mode, entering Terminal, and typing the command
xartutil --erase-all
You’ll be prompted to confirm that you want to clear the data. After confirming, quit Terminal and shut down.
That what I mean thanksA quick web search turned up: https://eclecticlight.co/2018/07/17/firmware-the-smc-nvram-and-t2-chip-reset-and-maintain/