I doubt Iranian ships with 76 mm cannon are candidates for engagement with a ship mounted cannon of your own. It would be better to use an ESSM or NSM instead. The Oto Melara 76 mm DART/STRALES is certainly a nice system and allows for engagement of small maneuvering objects, according to the manufacturer at ranges of "more than 5000 meters". However, the USN's 57 mm MK110 still has a much higher ROF and also has similar ammunition in the form of the Mk295 ORKA which has a dual imaging and laser seeker and should work at ranges of up to 10 km according to the manufacturer.
Given that small attack craft are an important threat in certain regions, it makes sense to have a specialized high ROF weapon to deal with these. What else would you use a 76 mm or 127 mm naval cannon for these days? In the anti-ship role cannon lost their primacy to missiles, same for air targets. The fire support role against coastal targets is limited and forces the ship to come within range of possible enemy anti-ship missiles.
Edited by Daan, 02 May 2020 - 0739 AM.