Which is essential for the longevity of a platform. You can’t further develop the JVM if you are bogged down by code depending on the internals. Encapsulation by modules is hugely important, and if we are honest, anything that depended on internals were prone to bugs anyways. Sure it sucks, but they will update sooner or later
this has been the case in the past, but Java is gritting its teeth and making some breaking changes in the JDK11/16/18 era.
libraries that mess with the unsafe/internal namespaces are the most prominent example - there are a ton of legacy libraries that are going to break from that change unless updated - but there's also a big push for modules and for classes to encapsulate themselves more strongly.