College degree vs self-learning.

Answer 1

formal schooling is always better

Answer 2

same as going to school or being home schooled.
if you don't have a college degree, your only proof of your knowledge is projects or work-ex (if any).

Answer 3

I'm not sure how it works in your part of the world (I am in Canada), some places do look at any publicly available repositories of code you have developed (e.g. github, bitbucket etc.) and value an individual's personal effort at learning and writing good code.

College/Universities (in my experience) do not teach how to code well, companies often run shoddy, poorly written code so the ability to show that you not only have the ability to write code, but write code well is something that I personally feel is extremely important.