Swimming in places like Cid Harbour is a bit like swimming in the back blocks of
Sydney Harbour, or Broken bay. Most get away with it, but there are much safer places to do it.
Through the 70s, & to the mid 80s I was running tourist
boats there. We were never very concerned about sharks, other than to take normal care, & avoid murky water. We were much more worried about
marine stingers, jelly
fish, which were in waters closer to the mainland.
On the outer reef there were always numbers of smaller reef sharks of difference types. They could make landing fish caught there difficult on occasions, but we rarely saw large sharks.
There appears to have been an explosion of larger sharks recently, of types almost never seen up there previously. What else would you expect when many are now protected species.
Only humans are stupid enough to protect their predators.