Yes, this is the precise reason that Node was so popular! But the same language doesn’t necessarily mean the same stack. Yes, you can combine Node with React. But I believe this (and possibly Vue) are your only options to make an isomorphic app (same code on client and server) right now. JavaScript is great, but is the combination of JavaScript and Node and React the best possible stack?

In my opinion, there is definitely room for competition with the current JavaScript app-building frameworks (Angular/React/Vue). Blazor is an experimental technology that could fizzle out by next year, but as an application framework an isomorphic C#/ASP.NET stack adds a lot of depth.