1 Great white, 2 Grey Nurse 3 can’t tell but it’s no dolphin. How dangerous a shark is depends on some easy to see factors and 1 less obvious. Its not just size although the damage a 2m shark can not do the same damage as what 4m one will and is very unlikely to attack something the same size at itself. Smaller sharks can bite at hands and feet and its not that these bite are nothing but rarely cause a fatality.
Usual food source. Sharks that hurt smaller fish only bite people by mistake but those that hunt bigger prey like seals are far more likely to bite us.
The mouth mechanics of species makes a difference to the risk. Hammerheads look threatening but their mouths are slung under their heads and its small compared to body size. Big Wobbys have large mouths but small teeth and tend to bite and hold, Whites with big forward mouths, big teeth wide gape use head shakes to disable prey.
Behaviour plays a big part Tigers don’t like their prey facing them and can be faced down if too close, Bulls in dirty water bump things and if they move bite, Whites hit hard and fast from behind. You can also get territorial aggression, when another hunter like a spear fisher is in what the shark considers as its turf.
Hunting times, Most sharks are opportunists but have preferences grey nurses are little threat during the day but you CANT dive with them at night completely different animal. White's prefer lower light dawn and dusk, Bulls will hunt any time.
Recent history of hunting success, this is the more complicated but I think the critical factor. A fat shark full of fish is little risk to anyone no matter the size or species. They don’t care about us whatsoever. But a hungry shark in an area of low food supply or one that has failed to catch prey starts getting desperate. If it doesn’t eat it dies, so they start bite at anything that even might be food. Sometimes that’s us.
On land its easier to see the low food source factor, in the ocean its harder, not impossible just harder.