A great photograph is made by a person who is both skilled in the eye and skilled with their equipment. The quality of the equipment matters. If the eye visualizes a perfect image, but the skill with the equipment or the physical limitations of the equipment itself can't fulfill the need for that perfect image, that's a problem. Yes, you can take beautiful images with kit lenses, but the more sophisticated your equipment becomes, the greater range of images you'll be able to capture, and the more skilled your eye will become at recognizing great images before they become great photographs. Equipment simply expands the breadth of your photographic capability. That's why we choose what lenses we place in our bags before a shoot. Because if it was 99% skill, we'd just throw on a 18-55mm and go shoot. For a hike, we may choose slower zooms for their light weight and range of focal lengths. For a portrait session, we might take medium and telephoto primes with fast apertures. But not having a range of equipment is only limiting if one seeks to expand beyond the capability range of the equipment he or she has. Buy a macro lens and you'll find yourself taking photographs you never thought about before, images your eye had never conceived of. That said, never expand your equipment beyond your ability to be technically skilled with it.
As light is captured by the triumvirate of film speed, aperture, and shutter speed; a good photographer is made by the triumvirate of visual acuity, technical skill, and equipment. The actual percentage breakdown is completely dependent upon the individual photographer and their needs.