Really interesting story... but I think the age old adage of "as long as I'm happy" should apply here.
$20k for what amounts to a short story is an insanely good and fair price, compared to the market rate. I know he says he negotiated badly but I don't know how much more he could have obtained, as $20k _is_ a great sale. It does suck to see Minecraft later get sold for billions and "only" have your $20k but I have a feeling (and he basically admits) he was happy with the $20k at the time.
$20k for what amounts to a short story is an insanely good and fair price, compared to the market rate. I know he says he negotiated badly but I don't know how much more he could have obtained, as $20k _is_ a great sale. It does suck to see Minecraft later get sold for billions and "only" have your $20k but I have a feeling (and he basically admits) he was happy with the $20k at the time.