I just happened to notice the following in javax/swing/SwingUtilities.java
===

public class SwingUtilities implements SwingConstants
{
    // These states are system-wide, rather than AppContext wide.
    private static boolean canAccessEventQueue = false;
    private static boolean eventQueueTested = false;

===

So far as I can see these 2 variables are un-used and have been un-used since at least JDK 8. So clearly no urgency :-), but I should do some more checking and delete if appropriate.