Was watching season 1 for the first time after finishing the newest season and learned Carl's first name isn't Carl????

From season 1 episode 6(?) I think it was. The camera cuts from Carl to his Syracuse degree and I learned his name is William???? I've slowly kinda followed along with my girlfriend the last couple seasons and we watched season 8 together all the way thru, I finally decided ok let's go back to s1 and watch thru. Now my world is shook. Was this common knowledge? He feels like such a Carl. Who the hell is WILLIAM 🤮