I'd recommend using JS (or TypeScript) for a while to understand how Node.js performs before making comparisons like this, because it does surprisingly well und

I'd recommend using JS (or TypeScript) for a while to understand how Node.js performs before making comparisons like this, because it does surprisingly well under the kind of load most web or API servers see. The standard library and the package ecosystem use asynchronous IO for nearly everything, which makes multithreading almost irrelevant, and the V8 JavaScript engine is extremely fast. .NET makes it harder to do asynchronous IO, but easier to do traditional multithreading. I'm hesitant to say whether I think the average server running on .NET performs better than the average server running on Node.js, but I'm confident the performance difference isn't as wide as you might believe, and Node.js might even have the advantage.