This is a quick view into your configuration drift across your cloud environments. Clicking on one of the concerns will take you to the configuration drift(s) related to it.
If the concern is gray it means that it is a part of a team to which you do not belong - the user can view the drift but will not be able to acknowledge it. If the concern is colored then the user is on a team that involves that drift and can acknowledge that change in OpsCompass.
You can turn on/off managed concerns in OpsCompass to control the types of drift you want detected.
Additional Resources:
How do I view drift that has already acknowledged?