TLDR: CLO > GC
CLO is part of the C-suite, a top corporate officer who probably sits in on Board meetings and is aware of and has a role in major company decisions. Most companies don’t have a CLO unless legal issues are a core part of their business. The position does not necessarily involve active or full-time practice of law, there are executive and management duties as well. The CLO reports to the CEO or to the Board.
General Counsel is the head attorney overseeing all of the legal operations and legal staff, as well as managing and dealing with outside lawyers and firms. They report to the CLO if there is one, otherwise to the CEO — though, representing the company, they technically work for the shareholders and take orders from the Board.
If there is a CLO but no GC, the CLO will take on GC duties as part of the position.
It’s a little like the difference between CTO and Director of Engineering. The CLO is in charge of legal strategy, architecture, advocacy, and big picture items, whereas the GC gets the legal work done.