First of all, all the rules are not applicable for each forum. You can advertise your website in classified but not in any other forum, you can start a post with just an image or video (without any further comment) in video gallery but not in PA.
Ahmadis insulting prophet? I am not sure why would they do that? Prophet is prophet per their belief too, just not the last prophet. Anywhich way, if you see that happening, you can always report the post or start a thread here or PM Lusi or other mods.
Sorry dude, as much its violating your right of freedom of speech, the rule is going to stay. Maybe you know how to carry a conversation without throwing insults but not everyone can, so if it gives you any comfort, let me assure you that rule is not for you, its there to stop others.
and btw, last thought. You keep saying that I am protecting ahmadis. is this your way of admitting that ahmadis were attacked by non-ahmadis, hence the protection?