Both. A CS degree is learning and not just a bit of paper. It will give fundamentals and breadth, but not necessarily depth because they have to cover so much

Both. A CS degree is learning and not just a bit of paper. It will give fundamentals and breadth, but not necessarily depth because they have to cover so much ground. It doesn't teach how to code, they teach how the systems work. Self learning can give you the depth in an area that interests you, and provide the experience to debug and live with code you produce or to take on existing systems by contributing or interacting with OSS. They are not mutually exclusive... If a CS degree is available to you, do both.