I understand why you might feel this way, but there are several reasons to stay at the programmed pace.
The transition is difficult no matter how many classes one takes. The pace and volume are both higher. Fewer classes doesn’t really ease that like it feels it should.
Then the student has to make up that time overloading somewhere.
Finally there’s registration priority. Many schools program registration by academic progress.
I certainly wouldn’t overload first term, but I wouldn’t take fewer classes than were recommended.