1. Type checking is slow (this problem scales with the size of your project also which sucks) 2. Lack of proper build system ecosystem (as compared to Maven/Gradle/etc) 3. Ecosystem is poor 4. Packaging and module systems are poor (import side effects, gross)
If you tackle 2. you can also work around 1. Best way to do this at this time is to use the new Bazel rules_js/rules_ts ecosystem. This will result in lowering the amount of time you spend type checking and transpiling things making it tolerable.
3. and 4. however are just things you have to live with if you go with Node.js.
#3 is also a pretty wild take, in my experience. Maybe you have some pretty particular needs, but I very rarely find that I don't have what I need in Node.
#4, I'll give you--but if you're going to stan for the JVM, I hope you've never run into a static class initializer with side effects, because I've seen them about as often as I've seen side-effecting imports (which is to say, not often). I gather that they used to be a lot more common in Node, but I cannot think of a library in my usual stack, or even that I've used recently, that has side effects in that way (modulo development-environment stuff which leverages that kind of cursedness intentionally).
None of my debugging output includes JS lines because I pack source maps, which TypeScript happily includes.
Multi-threading isn't complex, because there isn't multi-threading. There's coprocessing via Promises, and there indeed are a lot of Node developers who think you don't need locking functionality because it's not multi-threaded (there was an absolutely bonkers discussion a few years ago where a JS developer insisted you didn't need locks), but whatever, they think that about other languages too, use async-lock or whatever.
"Maturity" is a word that means different things to different people. There is not a consensus-best-choice framework like Spring Boot in Node. Which leads people to doing things like "I'll use Express!" and now they have interesting problems all their own. But the tools are there and they're excellent. Fastify is perhaps The Best web framework I've ever used (other than perhaps Python's FastAPI, which makes me wish I liked Python enough to write it because that seems like a Right Answer in itself), and it has only gotten better with v4 allowing you to engage with type providers to create an end-to-end, automatically typechecked route declaration framework. It lets you do stuff like this, where you specify a request schema as JSON Schema (encoded via typebox) and it'll statically derive the TypeScript type for you whilst also using it for request schema validation:
https://github.com/fastify/fastify-type-provider-typebox#exa...
The tools are there and you do probably want to invest a little time in understanding what they do and what their tradeoffs are. There's value in that, for the way I write code and the stuff I enjoy building.
Overall, I'll trade some compilation niceties and even some (but to be frank, not much) performance for a vastly more productive environment in day-to-day use. I really like the JVM. I've been using it professionally for twelve years. I also like the CLR. I did Google Summer of Code for the Mono Project in 2008, I've been around. But the day-to-day of writing code in the dominant languages on those platforms for things other than CRUD does frustrate me, and the general-purpose languages on the JVM and CLR present difficulties in using the type system to effectively encode intent makes it much harder for me to write software that can guide other people to not misuse it. So for me it's worse both at library-writing and at getting-things-out-the-door. (I still do gamedev experiments in Java or Kotlin, though, because libgdx is seared into my brain.)
