The first programs were written in binary/hexadecimal, and only later did we invent coding languages to convert between human readable code and binary machine code.
So why can’t we just do the same thing in reverse? I hear a lot about devices from audio streaming to footware rendered useless by abandonware. Couldn’t a very smart person (or AI) just take the existing program and turn it into code?
It’s not impossible, just expensive. How much money do you want to spend?
To your point, the programs are already in code. Machine code. Taking random machine code, and making a human readable, that’s the trick