It's rather that you seem to have missed what I've been explaining here in other comments.
It'd be highly detrimental to Iran's national interest if a regime led by a megalomaniac and strategically allied with Tel Aviv, which has a record of cooperating with the latter against Iran, and which is blinded by hollow zionist promises of "unification" with Azari-speaking provinces of Iran, came to grab the last stretch of border between the Sea of Tabarestan and northern Iraq that escapes its control or that of its ally and NATO member Turkey.
Hence why it's a pressing matter of national security to Iran, why Iran's territorial integrity would be threatened by such a development, and why Iran would respond to it.
Iran proved her aversion for war by displaying tremendous amounts of patience towards the Aliyev regime. The ball's in Baku's court. If it respects Iran's legitimate red line, the area will remain peaceful, if not then prepare for retaliatory action.