Complex sentence: While respectful of the work of historians, he asserts that the written record misses important aspects of the past--he asserts that one can't simply read about the past, that one needs to experience its materiality.
Split into simpler sentences: While respectful of the work of historians, he asserts that the written record misses important aspects of the past. He says that individuals can't simply read about the past, but need to explore its materiality.