Western New York’s largest health system late Tuesday announced a leadership change at the top of the organization, which came as a surprise to many in the community. Kaleida Health’s new CEO is Don Boyd, who succeeds the retiring Bob Nesselbush. Boyd, 50, had been serving as Kaleida’s president and chief operating officer since 2019, overseeing day-to-day operations across the $2 billion health system, which employs more than 10,000 people. Boyd also will maintain the role of president in addition to CEO. Nesselbush, who is 57, joined Kaleida Health as chief financial officer in April 2019 after spending 24 years at Rochester Regional Health. He was named CEO of Kaleida…