The linked article quotes plaintiff's attorneys alleging that Mr Fetzer is "mentally unwell." (We have to walk on eggshells a bit since Fetzer is a member here and our discussions of him have to afford him the protection of the MA.) From the nature and context of the statement, I gather this was a point brought up in court. If so, and if supported by evidence at trial, then the jury may have considered it a mitigating factor in the damage award. But in a larger sense, I have no idea where a $450,000 award fits in the spectrum of what was reasonable and expected in such a case.
Reading further in the link, it looks like Alex Jones remains the real target. Mr Pozner's attorney's say Mr Fetzer's unspecified mental condition was known to Jones and that Jones should have exercised better judgment before amplifying the crisis-actor claims to a wider audience for profit. I'm not sure I grasp the legal strategy here. It seems that if Mr Fetzer has been deemed mentally fit enough in Wisconsin to be liable for damages, that would tend to estop an action in Texas predicated on a claim that Jones' negligently failed to regard Mr Fetzer's mental fitness before relying on him as a source. It seems more of the facts of the two cases are needed before we can speak intelligently about the propriety of the award.