Actually, you are wrong. He does write off panspermia. This is the problem with such a badly written article. It's so hard to filter away the nonsense and get to the meat of the article.
"panspermia is an interesting idea but has no evidence to support it."
"panspermia is an interesting idea but has no evidence to support it."
That's a pretty clear write-off.
But none of this is my point.