oracle constrained by the GPL
Openjdk may not be quite so easy for Oracle to exploit because they're bound by the gpl on any external contributions. Without reimplementing everything themselves and somehow convincing the rest of the contributers to accept that, they can't simply force new licence terms without forking Java.
Any oem breaking the classpath licence deserves to be sued anyway but oracle probably have little scope to 'manufacture' infractions. Won't stop them trying. We're still pretty reliant on the courts deciding the fair use defence favourably and finally killing oracles case along with any future attacks they would inevitably make.