Why is there a big difference between measuring the internal resistance of ESD grounding and the internal resistance of equipment protection grounding?

I don’t know how you measured it. Logically speaking, the equipment protective grounding should not be so large.

The possible reasons are: 1. The internal protective grounding effect of the equipment is not good and it is not directly connected to the earth; 2. The selected measurement point is not a metal part of the equipment, and there may be an insulating layer on the surface