I think this is an odd view and one that doesn't generalize very well. On Netflix, for example, the top show profits off of the victims of Jeffrey Dahmer. Families of Dahmer's victims have expressed their displeasure and hurt that their loss is dramatized for entertainment and profit. Likewise, people accused the Kennedy assassination of being fake, 9/11 attacks were an inside job, and so on.

I cannot imagine the loss these parents have experienced. It's certainly a deplorable thing to falsely accuse them of faking that loss. I would support making it illegal and punishable by criminal offense to harass, or encourage the harassment of, the bereaved.

That said, we don't live in a society that protects victims from the cruel speech of others. Except, as it turns out, if the perpetrators of that speech are ideological and political enemies of the government.