I've had the good fortune to experience both sides of accountability coaching. Good and bad. Too many leaders practice reactive coaching or simply fire fighting coaching. This leads to conflict, poor morale, and high turnover. The best accountability coaching is proactive and planned.
One suggestion to turn your team around is to start with quick wins. For example, set 1-2 goals for each team member per quarter and 1-2 goals for the entire team. Do it in collaboration, do it consistently, and do it in a way that sets your team up to win. Follow up monthly to help, provide input, and encouragement.
Let me know how it goes! I've used this method with great results.