Yes, if you had a coiled optical fiber cable with a length of 300,000 kilometers and you could see both ends simultaneously, you would be able to observe the light delay.
In optical fiber cables, light travels at approximately 200,000 kilometers per second, which means it would take light 1.5 seconds to travel the entire length of the cable (300,000 km / 200,000 km/s = 1.5 s). Therefore, when a light source is switched on at one end, you would notice a delay of approximately 1.5 seconds before the light is visible at the other end.
Keep in mind that this calculation assumes ideal conditions and doesn't take into account any losses or dispersion that may occur in the fiber optic cable. In reality, there may be some signal degradation, so the actual observed delay could be slightly different.