I think I developed it as a young man and it pretty well turns itself on whenever I sing. If I don't want to use Vibrato, I have to actually switch it off but I have not one single clue as to how I create the sound.
As for those who don't like it, well they are usually the same people who prefer songs to be sung in the artist's "Talking Voice".
I'm guessing that to those people, distinct voices are like distinct flavours. You can enjoy them intensely for a short time but then dislike them with the same intensity when the novelty wears off.