The Goertz cables are flat and the conductors are closely coupled so as to increase the capacitance.
This is done to reduce the Characteristic Impedance of the cable. Their cables approach 4 and 8 ohms (depending on cable selection) and so reduce reflections in the cable depending on the impedance of the speaker.
Some may suggest that reflections at audio frequencies are a non-issue, but measurements that I and a team I was associated with (using a Time Delay Reflectometer) suggest that if you can get the cable to have a low CI, it will be more revealing.
So there can be a reason for high capacitance cables, and amp designers need to suck it up. The old Polk Audio wire was high capacitance and did mess with unstable amps of the era. But as at least one pointed out here, ESLs are capacitive as well and are often driven by amplifiers :)