Think of TypeScript as writing JavaScript with inline tests: It takes longer but it produces "safer" code (with fewer bugs)

Is it worth learning it? I'm sure type-less job offers will continue to exists in large numbers, so if you don't like it then don't study it.

Note: TS is generally not referred to as "testing", this is just my simplification. I've been using TS for years for everything and it has avoided a lot of bugs — which is something I notice when porting projects to TS.