There are only a few good hits for 12G protection.
You need FemtoFarad capacitance in the data levels to minimize eye-pattern distortion. So the best protection is the lowest junction and differential capacitance that is rated for IEC 61000-4-2 using the recommended layout.
There must be a margin budget for jitter or Eye pattern margin, that includes the EOS protection.
The PUSB3FR4 is 0.29 pF typ
The
TPD1E05U06 &TPDxE05U06 are rated at 0.42 pF to 0.5 pF typ.
RClamp3371ZC below is 0.25 pF typ. but only in a single port.
View attachment 186364
It is commonly known that diode capacitance is also proportional to ESR or Rs which determines bulk I*Rs rise for a common material property.