Yeah there's a JEP around deprecating access to sun.misc.Unsafe, but that's part of a larger effort including Jigsaw to push the Java ecosystem in the direction of modular builds, where more invariants are assumed to hold (e.g. " 'final' fields are actually final") unless explicitly opted out for each module. I would assume the lack of such guarantees in the status quo wreaks a lot of havoc with EA.

Profiling and debugging would be separate considerations -- I'm really not sure what limitations those impose on the JVM JIT.