The gig economy for business is not much different than any transformational disruptive technology. There will be many winners that achieve an early foothold in the new technology, gaining a significant advantage. Then there are those who will not be affected at all. There are also companies and industries that will possibly face significant disadvantages for decades.
The best paying gigs often require a highly specialized field of expertise in a robust growth industry. A high skill level requirement often reduces the number of direct competitors. The high level of robust growth means lots of job opportunities. Thus through supply and demand (remember economics 101 and the laws of the invisible hand by Adam Smith?) these factors work together to create an outstanding future until the number of high level professionals grows to meet demand, or the market growth slows down significantly, to a level that allows professional support to keep up. If your new in the computer field and at the beginning a new freelance gig career these to not only look good today, but the long tern position of these industries look to be longer than most carriers last.
A gig is a temporary and flexible job, on location or through the internet, hired as an independent contractor (often known as freelancers) for people or companies looking for specialized services instead of hiring full-time employees. Often one full-time employee can not handle the plethora of different skills needed. So, instead of having a full-time employee, you can (for example) have 4-5 gig contractors splitting the workload, with each specialist solving a specific task.