Formal education tends to lean toward the theory side of knowledge. Teaching things to yourself (self learning) tends to lean toward the practical knowledge.
You can learn both through either method, but each tends to give you a little more of one over the other.
You need is to understand that whichever route you’ve chosen you’ve probably gained a lot more of one side of the knowledge equation and need to spend some time acquiring knowledge from the other end to balance your education.
If you go to the 4-year degree route, you should realize that many people in the work force can already perform the specifics of your job better than you can. But it’s up to you to put in your time gaining the practical experience you need to complement the theory you learned. Don’t pass on opportunities to gain the practical while in school. Apply for that internship. Try to get a summer job in your chosen profession no matter what the specific job.
If you skip school and go straight to the workforce, understand that you need to acquire the big picture view of what you’re doing. Grab some books on the fundamentals. Audit courses at nearby colleges. Set a more formal path for your own education beyond the day to day. Be more active in understanding why different techniques work as they do. Devote some time to studying themes in your craft.
In the middle is the online education. Its formality offers a chance to learn theory, yet many online courses aim to get you into the workforce as soon as possible. They may not excel at either end, but they do offer you the balance in the middle.