Regarding the Redux example, there is certainly a better way to do it as you mentioned (and I think I did too).

My point there was that, yes, with a solid lead developer, you can avoid many of these issues. But, not every team has the luxury of having a TypeScript expert on the team.

The fact that you need to have a skillset in proper typing is an added layer of complexity that while you and I as developers find exciting, it’s not ideal when working on tight deadlines, projects with constantly changing requirements, or working with less experience teams.

I 100% agree that the extra code is worth it in the end, but how long before you see the benefits? At a corporate level with teams of 5–10 devs, yes, you will see the benefits.

A team of 2 or 3 working at a startup that can’t afford to devote a developer’s efforts to managing types, maybe not so much.

While I didn’t give the best example of TypeScript’s verbosity, it doesn’t take too much digging to see real world examples of unreadable type definitions.

Please know that I’m not saying any of this to bash TypeScript. Like you said, it’s tremendously useful, especially when working on large teams and dealing with APIs. However, code completion, easy refactoring, and less typos aren’t benefits unique to TypeScript in my opinion. You can get the same benefits with linting and an IDE.