HMS Sheffield was sunk by an Exocet from a Dassault Mirage two days later, most likely as revenge
Not really, firstly it was launched from a Super Etendard not a Mirage, secondly the Sheffield attack was the second or third attempt by the Argentinian Navy to attack the carriers using exocet, the Argentinian navy went to a lot of effort to get the Etandarts exocet capable and were intending on using them against the Royal Navy carriers long before the belgrano was sunk. If the exocet attacks were reveng then as advocated by most combat instructors they were trying to get their revenge in first.
. Critics are of the opinion that if UK hadn't been the first to sink an enemy vessel then none would have been lost on either side.
Critics are like arseholes....sorry no Opinons are like arseholes every critic is one. Sorry nope I'll get it right eventually ... Opinions are like arseholes everyone has one, ignore the opinions be guided by the facts. Given that the argentinian Navy was actively seeking out the royal navy carrier battle goup with three task forces and two air attacks on the day the Belgrano was sunk it was obvious that someone was going to come off badly. Unfortunately for those onborad the belgrano she was it. Perhaps ironically as of all the Argentinian navy ships she was best suited to survive a torpedo hit, as some of her sisters did in big mistake II.