TypeScript Origins traces how a language that started as an internal Microsoft project became one of the defaults of modern web development, told by the people who designed it and by the maintainers who eventually bet their own projects on it.
What makes it worth an hour is that it spends its time on the design arguments rather than the timeline. Gradual typing and structural types were not obvious choices; they were concessions to a language that already existed, running in browsers nobody controlled, in codebases nobody was going to rewrite. The documentary is candid about what those concessions cost and about how much of TypeScript's adoption came from the editor tooling rather than the type checker.
That trade-off is one I keep running into in my own work: the type system that wins is rarely the most correct one, it is the one people can adopt without stopping what they are doing.