The TypeScript team chose Gatsby for its new website due to its ability to handle larger sites while maintaining static deployment, which was necessary for their expanding documentation needs. Previously using Jekyll, they found its limitations in scalability and flexibility for larger projects. Gatsby's integration of a GraphQL API provides a robust separation between data setup and file generation, allowing for more introspection and a seamless build process. The team aimed to create a website that was as close to vanilla HTML, CSS, and TypeScript as possible, minimizing the need for runtime JavaScript. This approach benefits the TypeScript team, most of whom have compiler rather than web development backgrounds, by simplifying the codebase and lowering the learning curve. Gatsby's speed, achieved through techniques like pre-fetching and asset optimization, further solidifies its appeal, along with the extensive plugin ecosystem that allows easy adoption of new features. Gatsby's support for TypeScript, although not initially comprehensive, has been integrated with the help of community plugins and tools, making it a suitable choice for the TypeScript team's goals.