The Navy is just another vector launching missiles, the grain ships are not being attacked by the Navy. More resources to the Navy? , restrained actions? Yes. Attacking the power grid? Yes, that too. The Russian Navy is still going to be there doing things.They didn't change the overall outcome of the war, but they changed events in the short term.
Going off topic now.
Not in the short term, but in the long term. In short: the Regia Marina was ineffective (a long discussion here, specially about the convoys), before and after Alexandria, before and after Taranto. The Regia Marina moving north from Taranto made things easier, less enemy capital ships made things easier for the RN. Getting German submarines in the Mediterranean made things more difficult, it did not change things.