The ngEHT expansion will enable the array to make real-time movies of supermassive black holes on event horizon scales. These movies will resolve detailed structure and dynamics near the event horizon, bringing into focus "strong-field" gravity features predicted by General Relativity as well as the interplay of accretion and relativistic jet-launching that sculpts large-scale structures in the Universe.
Wouldn't it be hilarious to discover in the distant future that some astronomical object just happens to look blurry even at perfect resolution because the object is just blurry in appearance?