"But the fact that some geniuses were laughed at does not imply that all who are laughed at are geniuses. They laughed at Columbus, they laughed at Fulton, they laughed at the Wright brothers. But they also laughed at Bozo the Clown.” - Carl Sagan
If you want to see what someone who is credibly trying to predict events look at the work of Nate Silver or Nassim Taleb. When you obsess over one prediction by person most known for comedy and questionable personal statements, it's neither difficult nor inappropriate to put them in the clown category.
If Adams himself wants to build his reputation as a prognosticator, he can easily create a publicly-verifiable record of them and any questions of his ability will answer itself in short order. That he has not (to the best of my knowledge) done so makes him look like a huckster.
If you want to see what someone who is credibly trying to predict events look at the work of Nate Silver or Nassim Taleb. When you obsess over one prediction by person most known for comedy and questionable personal statements, it's neither difficult nor inappropriate to put them in the clown category.
If Adams himself wants to build his reputation as a prognosticator, he can easily create a publicly-verifiable record of them and any questions of his ability will answer itself in short order. That he has not (to the best of my knowledge) done so makes him look like a huckster.