Programming is fundamentally different from building a plant in a number of ways. To begin with, computer science theory is more akin to what you describe as "

Programming is fundamentally different from building a plant in a number of ways. To begin with, computer science theory is more akin to what you describe as "actually building the plant" in the sense that it's concerned with the details of algorithms rather than how to design software. Some schools make an honest attempt of the latter but it is in my opinion I haven't seen much useful come out of it. There's simply no replacement for reading other people's code. Let's also not pretend that academic merits guarantee anything in itself. I've worked with people who couldn't reason about even the most trivial data structures or complexity who somehow had solid degrees in that very subject. How they went about that I do not understand. I doubt you can reliably tell an autodidact programmer from a formally trained one. Computer science is much too young, and although we want to see us as just another math heavy engineering discipline, that's not all there is to it.