Fandoms in the social media age are nuts. They feed off of each other’s insanity.
I’m indifferent to Taylor as a performer. She has some really catchy tunes that get in your head. She won’t be at the top level of fame forever, but she’s had enough endurance where her music is the soundtrack for a generation, maybe two generations.
Even when her popularity inevitably wanes, she’ll always be in demand to some extent. If nothing else, in 10-20 years the nostalgia factor will kick in among the fans who grew up with her.