These are all labels. I might use the term denier because I will also show what they are denying.
It should be the same with cult - the claims you deride should be on show, and whatever evidence is produced examined and, to justify your use of the label, debunked by evidence.
Isn't this better than skipping all those steps while going straight for the most extreme label?
I don't even know what the 5G coronavirus claims are based on, because I don't know where they are allowed to post evidence (if there is any).