Not really. I read a lot of biographies (sometimes, multiples ones on the same person over the years) and I am always conscious that it is the take (or view) of the writer writing it and 'through their lens'. A good example of that is someone like Marilyn Monroe, whose story has almost become a total myth. Some books paint her as a substance addicted mess, others as a victim of Hollywood, and recently as a brilliant, savvy and sharp CEO type who knew exactly what she was doing, how much money she was making, and how to get what she wanted; a victim of the patriarchy; a dumb blonde, etc. Marilyn's sister's book was surprisingly one of the most grounded. The real Monroe's story has probably been lost now in the constant re-selling and re-telling. Also writers will often look for an angle, even if they have pummel the story to fit it or fabricate a little.
As memoirs go, the diarist Anais Nin spent years rewriting and re-editing her diaries until she could interest a publisher. At surface level you have this mammoth work on the life of a woman artist/writer from 11-73, on another level you have this embellished monument to narcissism, full of men who are in love with Anais, how wonderful and selfless she is, etc. Since she chose to focus on her 'emotional' life, the diaries aren't worth much historically or factually. Later, a lot of her life, as presented in the diaries, was exposed as a bit of a fantasy, a lot of the struggle was hollow as her life was economically propped up by her wealthy banker husband, which she had conveniently omitted, painting a picture that she's a single woman struggling through life and having multiple love affairs (some paid for, as she was wealthy enough to financially support some of her lovers).
Imagine how different TSP would be if it was suddenly revealed that Moth had a family trust fund?