PINE64

I have a project I'm working on that will be using a portable Thunderbolt 3 USB type-C display (hooray for only one cable!) and was looking for an SBC that would be able to drive it. I saw that the ROCKPRO64 has a USB type-C with DisplayPort 1.2, but I wasn't sure if that means it actually supports Thunderbolt 3 or not.

It is not compatible. There would need to be a Thunderbolt controller on board and those are $95 each at the motherboard manufacturer level...