Human beings are not a part of sharks' normal diet. Sharks normally avoid humans. That is why accidents to divers are so few. The Florida attacks you mention occurred mostly along beaches, where sharks can easily mistake bathers' arms or legs for fish. Sharks produce slowly and produce few young.
Many species are today on the endangered list.
Even the great white shark in South Australia and South Africa is now a protected species. The shark-feeding programs have helped develop an increasing respect for sharks and helped curb the commercial overfishing that has dangerously depleted their numbers.