You learn a lot in college. It's a structured environment where relatively well-curated information is supplied to you at a reasonable pace. You could find the same information elsewhere, of course, but it is often hard to know where to look or who to ask. Things like algorithm design, software engineering, and project management are very useful things to know. College will teach them to you. If you choose not to pursue further college, you should have a plan for teaching yourself.

Additionally, there is some perceived value in a having the degree. In a perfect meritocracy, if Alice and Bob have similar skills and experience, they should be treated similarly in the professional world. However, if Alice went to college but Bob was purely self-taught, the real world may well hold its prejudices against Bob.

Here is a personal anecdote of mine, which may be relevant to you. Not long ago, I finished a 4-year bachelor's degree in 3 years. On my resume, it lists a 3 year time span for this. I regularly get recruiters (both official company recruiters and 3rd parties) asking me whether I actually finished school, whether I was in a proper 4-year program, and the like. This leaves me in an awkward situation, and I am forced to clarify my circumstances.

People often joke about the value of a piece of paper, but sadly there may be some degree of truth to this one.