It would be very surprising that someone who went to so much effort to remain anonymous, and obviously had a sound grasp on how to do so, would be so careless as to log in to the forum from his public IP address and give other users the ability to view those IP addresses. Regardless, there was another thread about this not that long ago, where theymos stated he had changed his mind since the 2013 post which is quoted above:
I've rethought this, and I won't be releasing the PMs in 2021. I'm convinced that nobody will ever identify Satoshi no matter what info comes out, so I'm not worried about that, but I am concerned about the privacy of those who communicated with him. For example, kiba once said that he tried to send a gift to Satoshi, but Satoshi declined (reportedly saying something like "I already have plenty of BTC"). If the PMs for this exchange exist in the database and hypothetically look like this:
kiba: Hey, I know it's worth peanuts, but do you want a gift of 10k BTC?
satoshi: lol, no thanks scrub
Then it would put a big target on
kiba's back. (This is only a hypothetical example: in reality, kiba never published the amount he offered Satoshi, if any amount was even specified.) Even if I screened the PMs in advance for obvious stuff like this, it's impossible to find everything. Eg. maybe someone who talked to Satoshi was trying to be anonymous, but people are able to find him just based on his writing style or knowledge.
I do think that there could be historically-relevant info in there, so maybe if Bitcoin has taken over the world in like
50 years and historians are clamoring to know more about its history, I or my successors could be convinced to revisit the issue. Or maybe not; don't get your hopes up. (I still haven't read the PMs, BTW; maybe they're all really boring.)
TL:DR? Come back in 2068 and ask again.