Note that Google Pixel hardware is just fine and not evil, and they're looking at a different vendor for the next version anyway, because Google is making it so the Pixel will only run approved OSes.

You mean the Pixel hardware that employs a proprietary black-box security chip that they pinky-promised to open source but never did?

Oh no! A TPM without a driver! How can I trust any device that has a TPM I don't have a driver for?

The Titan chip does a lot more than sign and store keys. It also has storage (could contain malicious payloads) as well as an RNG and AES/SHA accelerators (which could be weakened/compromised), among other things.