Hi and welcome!

I think, when it comes to liking someone, therapists included, there are different levels of liking. In the professional relationship I need to like someone just enough to feel safe with them. Without some basic sense of safety therapy cannot progress for me. So, I'd give more importance to the feeling of safety over liking. Of course, that means that if I actively dislike someone I cannot feel safe with them.

So, yeah, to me it'd boil down to the sense of safety and also the trust that the T has good intentions and genuinely cares about my welfare.