I did look. Did you? That thread is a year of people speculating about if this would even be possible and a few prototype renderings. There is no evidence in that thread that anyone has even created a physical prototype, much less an actual working adapter.
> The elegance of the original model
I don't want elegance. I want sustainability, repairability, linux compatibility, and more than four ports.
Edit: I would have much preferred if they had maybe 1 or 2 TB4 expansion slots, then take those other 40Gbit/sec TB4 pci-e lanes and have a bunch of standard ports that are easily replaceable on the motherboard, which all together wouldn't even come close to saturating a single TB4 lane. Add up 3x USB-A/C 3.2 Gen 2 (10 Gbps each, or 5Gbps for USB 3.2 Gen 1), 2.5Gbps ethernet, 100Mbps SD card, and you're still well under the bandwidth for one of the 4 lanes. Then have the other pci-e lane do HDMI 2.0b.
> you're just diluting the speed of the interface and adding more steps between your device and the laptop's IO controller.
I (and likely most people) don't need 4 TB4 lanes at 40Gbps each. The ethernet expansion card that sticks out of the case is max 2.5Gbps. Where is the rest of that bandwidth going?