It's mean to make jokes about disabled people.
Jim is hanging out with a group of friends having a good time.
Jim wants to tell a joke.
Jim makes a funny joke about a sports team and their fans.
Jim makes a very insensitive joke about people with Autism.
His friend's explode with laughter making Jim feel very good about himself.
Jim is called an ableist jerk by his friend's, and he immediately feels regret and shame.