In short, because it is a very powerful technology with great potential benefits, which can be applied safely and sustainably.
GM technology is a very powerful tool with which the genetic traits of organisms can be changed in very particular and useful ways, it is (i) specific, allows the addition/removal/change of a particular gene(s), (ii) accurate, only the targeted genes are impacted at the level of intervention, and (iii) unrestrictive in terms of transferring genetic trait between organisms. It can therefore be used as a powerful research tool to elucidate biological research questions or as an innovative tool with which to develop novel biotech products.
When these GM products are developed within a framework that ensures their sustainability, they can effectively address social, environmental and technical challenges associated with biological systems in, for example, the health, agriculture or manufacturing sector. The unique potential benefits of GM technology is especially important within the context of climate change and the challenge of feeding a growing world population using limited natural resources.