I don’t understand why personally caring about the subject matters. My friend bought me tickets to the opera and accompanied me for my birthday bot because she likes opera - I love opera and she loves me. I do the same. I don’t feign interest in the thing — I think about what it means to my friend.
But you’re right about ppl not responding to even pretend that part of friendship is supporting/acknowledging things the other person cares about.
I’m not sure if this is a toxic Americans individualism thing where people are so used to being catered to and existing in their preferred echo chambers that they do not even know to friend or what.