I believe the shot of those books should stay not just because of what was been mentioned already, but it may send the wrong message when you’ve got the baddie Kylo Ren saying, “Let the past die, kill it” and then we’re led to think Yoda just ‘killed’ the past. Rey saving those books means both her and Yoda won’t let the past die.
I always saw the letting go of the past as something both sides did but in the evil and good way. Kylo kills his past so as to forget the love of his former friends and family so as to gain power. Our heroes are meant to learn and not dwell on the past and to rise above our past mistakes. Two very different sides of the coin of letting go of the past. Another element of “balance” in the film.
I agree, but I think there’s a difference between simply moving on from the past and killing it and everything it stood for.