In your own code, you can use FIRST and REST for lists.
But if you want to program you need to deal with that. Stuff was there before you and has a history. Changing things has a benefit, but also a cost. For a small community like Lisp, constantly rewriting code because some names change is not such a good idea.
Given that we can remember thousands of words in natural languages, a few hundred core words of a programming language is not such a huge hurdle.
Another issue is old books. I recently got value out of PAIP and On Lisp, and I still see people recommend A Gentle Introduction to Symbolic Computation. Stepping beyond CL for a second, car and cdr have even deeper roots; for example if someone is introduced to the wider lisp-like world through SICP they will also have to become comfortable with car and cdr.
In your own code, you can use FIRST and REST for lists.
But if you want to program you need to deal with that. Stuff was there before you and has a history. Changing things has a benefit, but also a cost. For a small community like Lisp, constantly rewriting code because some names change is not such a good idea.
Given that we can remember thousands of words in natural languages, a few hundred core words of a programming language is not such a huge hurdle.