The opposite of "cracked down" is "letting up or easing off." Instead of intensifying actions and enforcing rules, this means relaxing and reducing the amount of pressure, rules or restrictions. This might be seen as a more lenient approach to a situation, where there is a lowering of punishment, criticism or intensity of reaction. The objective here is to create an atmosphere of calm, acceptance and positive engagement. In the business world, instead of cracking down on employees, a boss may choose to let up on them, giving them more freedom and trust in their work without micromanagement.