This author [1] has a fundamental misunderstanding of cons cells and what their purpose is. Cons cells are a primitive. They are best understood in contrast to the C model where memory is an array, i.e. an associative map from integers (or at least some abstract data type with a total ordering) onto values which are also integers (or at least sets of objects that can be mapped into finite sets of integers).
The key difference between the C primitive and the Lisp primitive is that the Lisp primitive does not require anything to be mapped onto integers whereas C does. You have to be able to increment and decrement pointers in C. You can have a fully functional Lisp with no numbers at all. In fact, this was the whole point of Lisp when it was invented: providing a model for computing on symbolic expressions rather than numbers. There is a reason that the original Lisp paper was called, "Recursive functions of symbolic expressions and their computation by machine" rather than "Cons cells: a new computational primitive".
All of the "problems" with cons cells are not problems with cons cells at all, they are problems with punning cons cells, i.e. using cons cells to implement higher-level abstractions without properly hiding the fact that the underlying implementation is a cons cell. The exact same thing happens in C when you run off the end of an array or cast a pointer to (void *). These are not problems with pointers per se, they are problems with using pointers to implement higher level abstractions (like finite arrays) without properly hiding the underlying implementation.
Punning cons cells and abusing pointers have similar consequences: segfaults in the case of C, and (typically) "NIL is not a valid argument to..." errors in Lisp. Both of these are the result of bad abstraction discipline, not a problem with the primitives.
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[1] The author is Xah Lee, who is pretty well known in the Lisp community. He is widely considered a troll, an opinion which I personally share. I've tried to make my assessment of this post as dispassionate as I can, but I thought I should disclose the fact that I have a pretty strong bias.
The key difference between the C primitive and the Lisp primitive is that the Lisp primitive does not require anything to be mapped onto integers whereas C does. You have to be able to increment and decrement pointers in C. You can have a fully functional Lisp with no numbers at all. In fact, this was the whole point of Lisp when it was invented: providing a model for computing on symbolic expressions rather than numbers. There is a reason that the original Lisp paper was called, "Recursive functions of symbolic expressions and their computation by machine" rather than "Cons cells: a new computational primitive".
All of the "problems" with cons cells are not problems with cons cells at all, they are problems with punning cons cells, i.e. using cons cells to implement higher-level abstractions without properly hiding the fact that the underlying implementation is a cons cell. The exact same thing happens in C when you run off the end of an array or cast a pointer to (void *). These are not problems with pointers per se, they are problems with using pointers to implement higher level abstractions (like finite arrays) without properly hiding the underlying implementation.
Punning cons cells and abusing pointers have similar consequences: segfaults in the case of C, and (typically) "NIL is not a valid argument to..." errors in Lisp. Both of these are the result of bad abstraction discipline, not a problem with the primitives.
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[1] The author is Xah Lee, who is pretty well known in the Lisp community. He is widely considered a troll, an opinion which I personally share. I've tried to make my assessment of this post as dispassionate as I can, but I thought I should disclose the fact that I have a pretty strong bias.