Agreed. Straightforward arithmetic is the capability, in Lisps represented in such a way as to fit with the philosophy of the language.

It's not like the majority* of languages see infix (or prefix, postfix, postcircumfix, etc.) notation as a basic enough concept to allow defined functions to make use of it. Arithmetic always seems to be the special case. No operator overloading, but arithmetic is pre-overloaded. Parentheses of function calls are all you need to keep track of subexpressions, but arithmetic will have an arbitrary and large list of precedences.

*correct me if I'm wrong. I know a fair few languages but mostly deep dives into particular niches. That could bias me.