There's a platform-specific qualified export in
src/java.base/macosx/classes/module-info.java :
exports jdk.internal.loader to java.desktop;

This is for the benefit of a method in AquaUtils which seems to be
using that internal class rather than calling equivalent public API.

Moreover the method is used for one very dubious purpose

- // special casing naughty applications, like InstallAnywhere
- // <rdar://problem/4851533> REGR: JButton: Myst IV: the buttons of 1.0.3 updater have redraw issue
if (classExists(launcherClassLoader, "com.installshield.wizard.platform.macosx.MacOSXUtils")) return true;

I doubt this is relevant any more, or if we care.
Is looking for installshield classes how you would detect Myst ?
Since MacOs changed to the current flat rendering, does it matter ?

I think we should just remove the whole thing.