What enormous impact do billionaires have on the space travel industry

The enormous impact billionaires have on the space travel industry is that they have developed companies that have reached a high level of relevance and importance in the industry because they have designed advancements the government couldn't achieve.

Explanation:

To understand this answer we need to analyze the context. First of all, billionaires have found a niche to profit from the development. However, due to the lack of importance, the government gives to the space travel industry they can't do further advancements. Also, the government itself stopped impulsing the industry. That was the defining factor for billionaires to step in. They have made the space travel industry affordable and profitable, in such a way they plan to travel to planets without government support or financing. They have developed better communications, rockets, and systems that have made rockets land without a parachute, using only the rocket propulsion.