Well, yes, this guy is probably mentally retarded, but this should not be blamed on bitcoin. Any currency can be used by a pedo, and other illegal activities...
You're insulting mentally handicapped people by referring to that pedophile as mentally handicapped. That is politically incorrect and suggests that you would benefit from sensitivity training.
Your vilification of the mentally handicapped feeds into the negative stereotypes of them. I trust that the mentally handicapped community disavows any association with, or condoning of, unlawful behavior.
In these tragic times the bitcoin community needs to stand together, and not segregate the mentally handicapped. The mentally handicapped have feelings, and hopes, and dignity, just like the rest of us. Just because you didn't wear a helmet in school is no reason to discriminate against those who did or still wear one.