The examples on the wiki page still have structure in the expressions. Though, I grant it is tough to see what was intended there?

From the name, though, I would expect that they would still be fully developed expressions. Just as I would not think you would say the string "(1 2 3)" is the same as the list `(1 2 3)`. Specifically, the structure of it being a list of items there is a vital part of the s-expression.

I don't understand the point on calling eval on the list `(1 2 3)`. My point is you can still have a syntax error, even if you pass it a structured list. Nothing more. To that end, it is not valid code. This does assume "is code" meant "is valid code." But, that feels a safe assumption?

For fun, if you don't allow a distinction between the list `(1 2 3)` and the string "(1 2 3)", then you can also flat out eval "(1 2 3)" without error. But that kind of gets to my core point, that the string and the list are different things.