Yes it is. Read it again. He is not the one who conducted the steal, and he illustrates just what those who did conduct the steal have done in its wake, concluding that the Founding Fathers would oppose everything those people have done—how can you mention the Founding Fathers, the framers of the Constitution, with any notion that they would approve of the termination of the document they fought to establish? You cannot, quite simply.
I disagree with your understanding of what Trump wrote. In my opinion he is stating that because the Founders did not want and would not condone false and fraudulent elections the termination of rules, regulations, and articles is allowable.
This is made clearer when he writes“ UNPRECEDENTED FRAUD REQUIRES UNPRECEDENTED CURE!“ Obviously the Founders would not have included a cure for fraud which they did not envision being a possibility.