AI: Two of four Thunderbolt 3 ports in new 13" MacBook Pro with Touch Bar have reduced speeds.
Specifically, the two ports on the notebook's right hand side provide full Thunderbolt 3 functionality, but have reduced bandwidth, while the left pair retains full PCIe throughput.
That's going to seriously suck for those who prefer the smaller form factor. With all the tethering photographers have to do these days, this is a confounding choice.