I'd probably still prefer .Net, but ES6 and TypeScript have made nodejs pretty bearable for me. I'd prefer it to and maybe even argue it's a better platform for concurrency than Python at this point, even 3.5, for most situations.

The concurrency you get with async/await is nice enough and performant enough over 0 concurrency to make it pretty good. You don't get thread pools and it's not the fastest at single threaded processing.. And there is only one number representation which is a hassle forcing the use of BigNum occasionally.. The stdlib is a mix of callback and events and requires wrapping for good async/await consumptions and.. Well there are a lot of drawbacks.

C# on CLR is superior IMHO as a platform and language in nearly every way except... It's not JS. If you are moving around between a ton of stuff constantly you'll end up doing a lot of JS(and in my case TypeScript because I've successfully introduced it multiple times) due to frontend work and the employee common denominator.

Edit: This is a bit of a ramble. I don't think NodeJS is the best thing going. But while I personally would prefer C#, Go(depending on project), F#, potentially clojure, and etc after removing personal preference and adding in all the other factors that come in to play when selecting a technology that a team has to use and support -> nodejs/TypeScript is often a pretty good option.