My CPR instructors put it the way I wrote it to encourage us to spend more effort on getting the AED and paramedics there fast. If you do CPR before the AED/paramedics is on the way you are wasting time, but getting those has been started CPR is important. However this is clearly semantics, I think we are all in agreement that CPR is important.
Not all states have "good Samaritan" laws. Most do, but if you live in the exception you might suffer harassment after doing CPR, including go to court - odds are the court will throw the case out, but it will still be annoying to do the right thing in those states. Though even lacking such laws, the odds that anything will happen are low.