The refactoring bit is almost convincing enough for me. I'm a front-end developer with a strong background in JavaScript and React. They say Typescript is a superset of JavaScript, but I disagree. I feel like I can't write JavaScript anymore when Typescript is in the mix. React component declaration gets messy and ugly. Just the other day I tried to use "document.something"... nope, can't do that, because there's no explicit interface for "document". It feels like every simple thing takes one or two extra steps with Typescript, and sometimes those steps take me all day to resolve!