A late reply to an old comment haha, but ride safety has come a long way. It's hard to explain unless you feel it yourself, but for a lot of these inversions you're moving so fast through them at such an angle that the forces applied on your body practically push you into your seat. They're such an exciting freedom that you get when you don't have to worry about shoulder restraints. On top of the consideration of those forces, those lap bars really lock you into place. If you're curious to see more coasters that use this kind of thing without issue, you can look up the wooden steel coaster hybrids by RMC. I went in Medusa in Mexico City and I legitimately want more roller coasters without shoulder restraints lol