My experience with React has been different hence commenting here. That is just not true. I have used react with nextjs in the past but moved to remix. Moving to a new framework requires you to learn it, quite similar to learning a new language but it is much better than manually creating webpack loaders. I had a decent experience with nextjs but my experience with remix has been better.
I used Spring Boot at work and I have worked with backend libraries like Express(JS), Flask(Python), Gin(go) all the experiences have been much better than using Spring Boot. Java takes too long to compile, dependecy injection in Spring just seems to take forever, and overall Java is very very verbose. Just to create a stupid API, you have to create a new class for request, one for response, controller, service. I can do it if I am paid for it but using that for side projects, a big NO.
I think we have different ideas about what a good development environment is, and that is ok. We have our preferences and we can't argue with that.
I would like to comment on how you feel Java compilation is slow. Incremental compilation while developing is fast and doesn't affect my productivity (your experience may differ).
Triggering a single threaded full build with one of my services (1000+ files and 80k lines) took less than 30 seconds on my laptop (18s with parallel compilation). But I never do that locally, as incremental compilations are almost instant.
If you need to download dependencies and run tests, the number is higher, but that is not specific for Java
I used Spring Boot at work and I have worked with backend libraries like Express(JS), Flask(Python), Gin(go) all the experiences have been much better than using Spring Boot. Java takes too long to compile, dependecy injection in Spring just seems to take forever, and overall Java is very very verbose. Just to create a stupid API, you have to create a new class for request, one for response, controller, service. I can do it if I am paid for it but using that for side projects, a big NO.