No one does that. You go to school and learn numbers and basic arithmetic, which gives you all the formulas you need. And even illiterate people work out quickly the minimum they need to do transactions.
> This ability to abstract logic is what separates developers from users
Then everyone is a developer as everyone can write a serie of instructions which abstract action from context. It just that the computer is very limited and you need to be very precise. But what it can do, it can do it very fast. What is instant for us is an eternity in CPU time, and you can do a lot with simple operations if you can do a great number of them.
> Just like a developer's brain can think about a problem and come up with a solution using code, o3 generates a program (i.e., metadata) on the fly to solve the problem
Again that's not happening. You think about a problem and solves it by constraining yourself to the basic operations you have available (the APIs, languages, libraries, platforms). The code is just the written form of that solution. You can't invent operations that does not exist, you can only group them under a new name. Each set of names is another layer of abstraction that make it easier to write the code. But the constraints don't go away.
The code is not how you create a solution. It's how you instruct the machine to replicate the solution you came up with.