IME the average, unoptimized node.js server application already scales (performs) a lot better than the average Java server application just because node.js uses non-blocking by default io and an event loop architecture that works well for most applications.

Of course I imagine if the code is written with performance in mind, Java code can beat out node.js, but my experience is that out in the wild, most Java code is not particularly performant.

Just learn Go. Honestly it's pretty simple to pick up, especially now with the slices package. I can't imagine using a loosely typed language anymore, even with an IDE to baby me.