It's definitely safer, and it does see quite a bit of usage in areas of the world with high quality cycling infrastructure. The fact that it doesn't see more usage is just a testament to the fact that most urban planners around the world don't care much about keeping cyclists safe.
No In Australia it’s for the benefit of the tram https://en.m.wikipedia.org/wiki/Hook_turn the article seems to imply it’s otherwise for traffic flow and 1 country for the benefit of cyclists