I am with you here, it seems perfectly neutral question to me.

But this reminds me of a time when I went to movies with some younger family memeber and their friends. After the movie they asked each other if they loved the movie. To me love was really strong word. I wanted to say I liked it, not loved it but then I thought no need to be negative here. So I just said yes.

So when people ask did you like the movie, many people subconsciously say yes even if they disliked it.