I'll take a claim by claim examination and refutation a whole lot more seriously than a blanket dismissal of all fraud claims without any discussion of the particulars.
I'm not saying Trump won. I'm saying let's investigate and find out. Just broadly stating there's no problem and therefore no need for investigation of particular claims appears kinda fishy, right? If there's no wrongdoing then demonstrate that and embarrass Trump further. Seems like people who dislike Trump would be highly motivated to investigate and publicly prove him wrong point by point. So have a deep audit and do that.