> Writing a good codebase is IMHO a craft and should not depend on the language or a bunch of tooling.
Of course, relative to other code in that language you can write good code in any language and that is a useful and important skill. If you invest enough energy and craft, you can even write code that compares favorably to good code in any language - the Linux code base is a testament to that. Still, it is a fallacy to assume that all languages are created equal. Nowadays, next to nobody would argue that writing code in Assembler is a good idea. And even though it is now possible to write web apps with C (via webassembly) there is no movement by seasoned C programmers to conquer the web.
> If Typescript is way to go, what about Python, Ruby, abandon it, deprecated? Are those inferior languages compared to Typescript? Typescript is just another hype, very smart play by Microsoft btw.
While the truism "use the right tool for the job" is overrated, it applies here. Untyped, quick to write languages are excellent for small projects. When I'm writing Python as glue code, designing nicely typed interfaces is a distraction. Also, Python, Ruby and Javascript have base types with excellent usability. E.g. when you parse time sheet data, it is pleasant to return [(time.parse('9:00'), 'document project X'), (time.parse('10:15'), 'implement feature Y')]. But when projects grow every structure enforced by the language is a guarantee I cherish. You know, there is this special case in your time sheet parser where you return a (time.parse('23:59'), Null) element, instead of using the empty string, which made the code much more elegant. But months later, when you are refactoring the code calling the parser, you have totally forgotten this behavior and introduce a subtle bug. That's the time where I wish I had a robust type system.
TypeScript is great in this regard, as you can ignore all types if you wish and gradually add them later, when the complexity of the code base calls for it. Or you start with complete type coverage from the start if that floats your boat. Or you never introduce types and just consume JavaScript. Because of that, TypeScript is especially valuable for libraries: It gives the consumers of the libraries all choices. And it's also the reason the success of TypeScript is celebrated that much: Each new TypeScript enhanced library increases the effectiveness of the tool (and reduces the amount of `any` crutches).