"The language" has been "lessened" in various ways since the demise of Old English with no clearly deleterious effect. For every "lessening" there are innumerable additions and refinements.

The enforcement of the "may" and "might" rule is now pointless. Nobody is confused or misled by the "misuse," and, should they be, their interlocutor or editor can ask what precisely is meant.

Prescriptivism is usually a lost cause anyway, since by the time an alteration in usage becomes widely noticeable, it's generally too late to do anything about it.

Nor are the "misuser"s eager to accept correction.