Someone once asked the writer David Foster Wallace how he got to be so smart. “I did the reading,” he responded. Interestingly, nobody called me “smart” either before I started reading books and newspapers. I put the word in quotations because “smart” isn’t innate.
Professors assign such reading all the time. Yes, it’s tempting to skip the reading, and yes, you might be able to still get a decent grade in the class without it.
But no, you don’t get to be called “smart” without doing the reading. Your intelligence is on you.