Elite software developers definitely exist especially when you measure the magnitude of contributions made to the industry and how influential the contribution was. I would definitely place a guy like John Carmack in the elite class considering his contributions to many notable video games over the years. This type of measure is not all that different than sports where an athlete's greatness is measured through the number of championships won and individual stats and records. I would definitely argue that the difference in talent between a competent/average individual in software probably isn't as big as in sports. If you quantify how "elite" an individual is in software by their influential contributions to the industry versus championships won and records set in sports, you're definitely more likely to achieve "elite" status in software. Take Ruby on Rails as an example, DHH is a hell of a programmer considering he's built a multi-million dollar business in Basecamp and how popular and influential Rails has been to web development. Now consider the confluence of factors that allowed Rails to get huge. Things such as design, code quality, timing, marketing, luck, etc. all played roles to differing degrees. If you compared this to something like being an elite basketball player there are even more factors out of your control. Being elite in basketball is pretty much impossible. If you're 6ft and 180 pounds there is no way you can reach the level of greatness of a guy like Michael Jordan. In a sport like basketball genetics plays a huge role in establishing the base for an individual to become elite, and obviously a ton of hard work on top of those genetics too. If you don't possess the combination of height, athleticism, strength, speed, long arms, big hands, basketball intelligence, etc. there's absolutely no way you can reach Jordan or LeBron's level.
With every industry where you need some sort of specialized skill and are able to quantify influential achievements in some sort of way, there are always going to be elite individuals.