Because simply IIQ and IIR works only on the kill hit. and IAE works with the whole spell/attack thats why the ingite don't work before and still don't works.
And the patch notes clearly only talk about RF and not about everything else. So why everybody asume that it works with DoT dmg? where is it stated from GGG? or do you have some other patch notes which you read?
Fixed a bug where Righteous Fire was not correctly supported by the Item Quantity or Item Rarity support gems