I agree with this, having recently gone through the exercise of creating some "onboarding" apps for new grads using Spring 5 and XML, then again with annotations. All the underpinnings for a non-Boot application are still there and mainly sane.

Spring Boot absolutely yields write-once throw away, and you _must_ consider the source: Pivotal is a contracting shop, so it's in their interests to hook people into an ecosystem that they happen to be experts in. I'm surprised this fact is lost on most.