Just to be clear, I made a working prototype (and put a hyperbole in the title), I have a lot to learn still.

You can learn something practical like "embedded DisplayPort should be impedance controlled to 100 Ohms" without fully understanding the physics behind it.

AI can be very convincing. It told me to put the ESD protection as close the Ethernet connector as possible, so I put it between the port and the magnetics. This worked, but resulted in around 1% packet loss. When I moved it after the magnetics, I got 0% packet loss. This cost me a full revision, but I'd say this is the price to pay for not learning everything by the book.