Implementing MethodHandleProxies#asInterfaceInstance with hidden classes

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Currently, java.lang.invoke.MethodHandleProxies#asInterfaceInstance [1] is
implemented with java.lang.reflect.Proxy. After looking at its public API,
including Javadoc, it seems that MethodHandleProxies would benefit from a
hidden class implementation without changing its public API definition
(including Javadocs).

Recently, there is JEP 416 [2] for reimplementing reflection based on
method handles. This implementation utilizes hidden classes with method
handles passed in classdata and retrieved to condy, which allows generic
method handles (beyond regular constable ones) to be optimized in method
calls. Similarly, for MethodHandleProxies, hidden classes allow the
implementations to detach from classloaders and be freely recyclable; they
can use class data to store the adapted method handles (which can
significantly speed up invocations); and it can allow it to support
implementing single-abstract-method abstract classes in the future (as
discussed in its Javadoc) as well, with only minor tweaks.

Does this sound feasible? I want to ensure it is a good idea before any
implementation is attempted. If there is any issue with this vision, please
don't hesitate to point it out. Feel free to comment, too! If this looks
good, I hope an issue can be created for it.

Best

[1]
https://docs.oracle.com/en/java/javase/16/docs/api/java.base/java/lang/invoke/MethodHandleProxies.html
[2] https://openjdk.java.net/jeps/416