word usage - When do you use this expression 'I am not a fan of '

I understand the meaning when it is said like

'I am not a fan of Indian food or horror movies'

Here, you are a fan of things like movies, food etc.

but I do not understand why it is correct to say

'I am not a fan of negativity'.

'negativity' is not a tangible thing. Can we use 'fan' this way?