Voltage on the serial link
Consider the smallest resistors in size (taken from here): -

A typical 0603 resistor is rated at 100 mW and a safe power dissipation will be 50 mW. So, to dissipate 50 mW in a 49.9 kΩ resistor requires a voltage across it of: -
$$V = \sqrt{\text{power x ohms}} = 50 \text{ volts}$$
So, the question really boils down to how much voltage can the serializer produce? For certain, it will be a few volts maximum or it would potentially destroy the deserializer: -

Given that the deserializer cannot survive more than 1.9 volts on the input, the power dissipation can be seen to be trivial.