Does the comma operator have to be left-associative?

Question

According to this precedence table, the comma operator is left-associative. That is, a, b, c is parsed as (a, b), c. Is that a necessity? Wouldn't a, (b, c) have the exact same behavior?

Answer 1

Since overloadable operator, exists, no, it's not the same behavior. a, (b, c) could call different overloads than (a, b), c.