Not sure that it works, but if so, I would drop Apple products.

Yes. Consider this...

If you havent done elliptic curve and shs256 computations by hand are you taking custody? Its turtles all the way down.

While most will inevitably need to trust to some degree its possible to verify the components and source yourself for those listing a bill of materials. Devices like Coldcard and Passport use the Microchip ATECC608B and ATECC508A respectively, the details of which were leaked some time ago. One of the arguments against seedsigner is that its built on rsspberry pi which has proprietary components, but even still, when operated as air gapped many potential vectors are reduced or eliminated. Like a Ledger, it still needs to have physical security and be fully dissasembled to check for tampering and reassembled before use for the paranoid.

Let’s all just use coreboot and program our own FPGAs then?