In my opinion, as an IC, you can have a positive professional relationship with your manager. However, the power they hold over you ultimately makes it challenging to form a closer bond. While some managers may appear more casual, and others more distant, at the end of the day, they have the authority to fire or promote you at any time. This power dynamic creates an unfair trade-off for ICs, as they lack the ability to terminate or promote their managers. Once your business relationship concludes, it is possible to develop a genuine friendship. At that point, both parties are on equal footing at a human level.