Why not?
- It has simple, straightforward, and pleasant syntax/semantics. Except for a few tweaks here and there, there is no need to re-invent the wheel here.
- It is pretty functional, all that's needed is to add everything-is-an-expression
- It supports multiple paradigms (functional, imperative, OOP)
- Since it has no types currently, a _modern_ type system can be feasibly added, supporting concepts like result/error instead of exceptions, maybe/option, pattern matching, etc.
- It has easy-to-reason about async features
- It has a huge ecosystem; it shouldn't be hard to port many high-quality packages to a similar language
Now, the lower-level features are another matter entirely, but it shouldn't be too difficult to retrofit what we want, like multi-threading (maybe building on top of workers), utf-8 strings, and so on.
...Spoken like a person who's never coded anything meaningful or serious, if you can't even gauge the complexity and man-hours needed to create (much less port) high-quality packages between programming languages.
Talking about "man-hours" tells me you think of software engineering like an assembly line, which it is not.
There are whole lot of factors that might influence the time needed for such porting; the keyword in my comment is "similar". If the new language is a superset of the original language, minus a few warts, I'm not sure what should take so much time. For one thing, the architectural design of the packages (which probably took most of the original effort) remains the same.