no it's not wrong to disagree but I do think it's a bit petty to go on to a thread and say you disagree just because you can, even if you don't have a reason to disagree iyswim.
I think all points are valid, as I also pointed out on that thread, and I do think that some things on that thread eg, people suggesting going on to unquestionable sites to see if pictures are there are very unwise and even disturbing, but on the whole I don't see anything wrong with circulating a poster, as long as it's done properly, eg with knowledge of the family and in accordance with international law (a point I also made on that thread).
can I ask why you disagree with it though?