Big Mouth has a lot of heart. Watching this along Bojack is interesting, because Bojack is obviously meant to be emotionally devastating, but using big emotional reveals as plot points cheapens what they do and how deeply they resonate. It's pretty much written into the episode arc of each season (with that second to last episode containing some big reveal), and after the first two seasons it loses its emotional resonance.

Big Mouth can do an entire episode on a kid fucking his pillow and have that feel way more real than all the forced "silliness" in Bojack.