I switched from WPF, C# dev to Angular JS with Typescript and Web API with relative ease and I'm digging it. Typescript definitely helped though. I know I have plenty more to learn, but it's not as shitty as people make it out to be.
If you're using Web API (built on ASP.NET) then you're not using Node, which is a Web server written in Javascript.
But I do think it's cool that someone can transition from WPF to Web development with Angular without feeling too lost. Dynamic Web development used to be a very, very different ballgame from client application development.