I noticed the signature campaign on Donald Trump but I missed the later one on Kamala Harris but by this fact that mindrust runs two campaigns for two Presidential nominees, it's fair enough and he did not skew to any nominee between these two ones.
Did you read the thread for the Kamala Harris thread? That signature campaign is
IMO, nothing wrong and that generally the discussions with Trump on Bitcointalk are specific enough and has some sort of connection to Bitcoin. We aren't here to say whose opinions are right or wrong, so I don't think there is any policing to do here.
Similarly, with signature campaigns, the signature space is a free space and each user should be entitled to having the liberty to display whatever they want. I probably wouldn't take too much of an issue with it and just ignore them if they're obnoxious on the forum.