But since many of my closest friendships have grown out of us being fans of the same stories and/or celebrities, I see the upside.
People who have parasocial relationships with the same public figures as me often have a lot of other things in common with me. & we have a lot of shared background knowledge about the same subjects that we can obsessively discuss to pieces.
I have occasionally fallen into the trap of trusting someone too quickly because we share a fannish interest, but it's rare.