I think a lot of people fundamentally misunderstand Tenna's arc.
His issue isn't that he can't move past being a TV that desires to be watched. His issue is that he clings to the Dreemurrs and can't move past THEM. What gets Tenna to change is Susie telling him that he doesn't have to take being thrown away. Tenna's flaw was that he's spineless and takes whatever's thrown at him, his growth is about being more open about what HE wants for himself.
That's why he tells Kris and Susie to find a new home for him. He wants to be watched and that means movibg on from the Dreemurrs who don't watch him anymore. He doesn't mind if he doesn't see Kris anymore, he realizes he can find happiness with new people.