Olivia’s friendship with Basilio is important as it’s that very relationship that resulted in her joining the Shepherds in the first place. Regardless of which units you like to use, which supports you end up exploring, Olivia’s admiration for Basilio remains an important, canonical part of her character.

On the other hand, Bernadetta has no canonical, unyielding affinity for anyone. She starts the game a blubbering mess, and she ends the game a blubbering mess. Her supports are ultimately meaningless ‘what if’ scenarios that stop being relevant the moment the conversation is over. There isn’t a single moment in Three Houses’ story where these ‘friendships’ are shown to be an important part of her character. She doesn’t know Felix unless you look into it. She doesn’t know the Death Knight unless you look into it. She doesn’t reconnect with Yuri unless you look into it.

Bernadetta is supposed to be the quirky character. That’s all. Having a plethora of temporary, superficial friendships that play out like shitty fanfics doesn’t change that.