Yes, you are allowed to do that same way you are allowed to Que up to LFR as a tank and leave after first boss. Or before that.
Were you so offended by a whisper or what? Otherwise I am really confused about where is this "audacity".
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They fixed it by increasing drop chance in m0 and m+ by a lot. Unlike raids, it's spammable content, so it only makes sense for the items not to drop 100% otherwise, it would make as much sense to make all drops 100%. It's an RPG, regardless of what people claim it to be and farmable easy content dropping rare powerful item is consistent with other RPGs. TBF I would not know why would anyone be spamming normal, but it's up to them.