I'm not convinced of TS as of yet for my needs. The vast majority of bugs and complexity in UI code seem to come from state management, asynchronicity, complex validation and the like. Static typing doesn't help with any of these or at least not to a degree that is sufficient. TS also doesn't seem to help at all with performance, which I find to be the most important trade-off for introducing types and the implied complexity.

I'm heavily biased towards small teams and small to medium programs though. I can at least imagine how TS improves ad-hoc documentation in some cases, which can definitely help in the "maintaining the code over a long period by different people"-scenarios.