They usually cannot write code from scratch, or when they do it contains a huge amount of plumbing copied from other familiar codebases without any reason for its purpose. It's kind of like they can read a foreign language, but they cannot speak it. Or maybe a parrot who can produce the sounds without the meaning.
I do think Google has caused some of this. But the other secret, I think it's how most people program by default. Animals largely learn by copying. The deconstruction of concepts to primitives, and synthesis of these primitives into new ideas if a very academic way to approach things. Centuries have proven this approach is superior, but it takes a huge amount of effort, and many things are lost in this process. (Ever do a physics problem with spherical cows?) With the rise of self-taught programmers, you will see more take this copying approach than the academic redistillation.