That's correct. I have never claimed that /dev/urandom is truly random.
I just wanted to clear out the 'how to be sure that dice rolls are truly random' question.
More precisely my statement was:
This is way more random than your brain or any dice rolls can ever be.
Fair enough.
And that's still my opinion. Humans tend to throw the dice in a similar motion each time. Especially with hundreds of rolls.
The outcome will be less random. And the brain being one of the worst sources of entropy should be commonly known, at least if you really need a random number and are ready to spend a few minutes to read into this subject.
I have my doubts about the first -- at least when someone tries to properly roll the dice and not just fake it -- but I absolutely agree with the brain being one of the worst sources of entropy (and real world attacks seem to support that claim).