First is familiarity: Minecraft remains one of the most played games of all time. Its simple interface combined with a focus on creativity - not competition - makes it appealing for young minds to investigate. It also offers the benefit of highly customizable and configurable code that allows anyone with the right skills and knowledge to make a difference in the world.
Put simply, Minecraft is the foundation providing the solid foundation children need to master more complex coding skills, such as Python or Java. It lets them eventually write mods and programming that alter the Minecraft world or create completely new experiences.