Comment by Cthulhu_

There's the blog post (by Anders Hejlsberg, the author of Turbo Pascal, chief architect of Delphi, currently lead architect of C# and a core developer of TS; I'd say he knows his languages), but they also posted FAQs, here's some good reads:

The blog post: https://devblogs.microsoft.com/typescript/typescript-native-...

Why Go? https://github.com/microsoft/typescript-go/discussions/411

Why a port instead of a rewrite? https://github.com/microsoft/typescript-go/discussions/410