I think the point is that you can write your code using ES6 and ES7 and the TypeScript compiler allows you to output ES6 or ES5 compatible code if you want to make sure it runs in older browsers as well. You can do that with non-TypeScript ES code as well but you’re bound to use another transpiler. With TypeScript you get it „for free“ since you need to compile your code either way.

Ah yeah, kind of like how I get a drink for free if I get the hamburger menu, even if it costs more? Kind of weird perspective, but I can accept that it's something zealots tell themselves so "we're doing it differently" actually computes for them.