Adewale Abati discusses how online IDEs like CodeSandbox allow developers to build and collaborate on code directly in the browser without needing local installations or downloads. Some benefits of online IDEs include accessibility, collaboration, mobility, quick start times, and flexible development environments compared to traditional offline development. While online IDEs still have limitations for complex projects, their capabilities continue to expand through features like mobile development environments, large shared projects, full stack projects, and enhanced collaboration.