Dr. Champ tells Bojack that he has heard all of his stories and proceeds to talk about hearing his dream of a dinner party. This is foreshadowing of the dinner party in The View from Halfway Down (2020).
The "Sad Dog" meme that Princess Carolyn creates of Mr. Peanutbutter sitting on a park bench is a parody of the 2010 "Sad Keanu" meme of Keanu Reeves sitting on a park bench.