She has social media but it's not managed by her. Her team manages all her social media accounts since she's a celebrity, and she probably posts an Instagram story every once in a while so people think she's the one using the account. But Briar doesn't really care about social media haha, she's the least chronically online person in the universe LOL

She uses her phone to message people (mostly Rose, Oleana, her manager, bodyguard... she doesn't give her phone number to many people because of security reason and also because she doesn't like people she's not close friends with texting or calling her 😭), do some research (her storage is mostly science book PDFs, research files, etc) and to take photos of her Pokémon and herself with her partners every once in a while.

Okay, thinking about it, maybe Briar does use her social media accounts (mostly Instagram) once in a blue moon. She would post a picture of her Pokémon doing something cute. And when her relationship with Rose was made public, she started to post some of her pictures with him. Actually Rose uses social media more than her, even if he uses it in a middle aged man kind of way lol 😭 he posts stories with Briar sometimes