You can get away without using Spring and do quite fine, but there's definitely a risk that if you invest in the JVM ecosystem you'll get hired to work on Sprin

You can get away without using Spring and do quite fine, but there's definitely a risk that if you invest in the JVM ecosystem you'll get hired to work on Spring. (alternatives like Vert.x, the less-annotation-heavy quarkus, etc). For Java web dev I actually like Kotlin better - ktor is pretty nice.