Tell me HN, what are your thoughts on this? Do you believe it's absolutely necessary to be a CS major to be competitive in the technology world?
Can the same result happen for someone who isn't a CS major but goes through all the hoops to teach themselves?
The features of a formal education include guaranteed access to experts [for some definition of 'expert'] and a proven set of priorities [for some definition of 'proven']. The downside is less potential breadth since standardized systems are standardized.
The real question is what does 'make it' mean? For some people the piece of paper matters. It's a goal with social and personal significance and there is nothing wrong with that. If 'make it' is tied to wealth...well it's easier if you were smart enough to pick rich parents.
In the end it depends on what you want. And in any event, while a CS degree won't necessarily make anyone good [for some definition of 'good'] it may open opportunities and if they are good a CS degree will probably make them better, and almost certainly not make them worse.
Good luck.