You are so very right and she was probably a very nice person, ( unlike some other opera " divas " who I won't name ). Very sad that there are not that many recordings of her available.
My God, this is the kind of performance that makes you uninterested in comparison and rating and critique, it's something profoundly honest, real and unique.
That is because too many sopranos started singing things ppp. This can be shaded way down into a mosquito at parts but live in the theatre it gets lost and sounds weird. Frankly I prefer the Verdi fuller piano. Nothing gets lost and it’s audible.