This study has been reviewed by other researchers, the original study chose an industrial toilet with a power flush. Notice how this toilet doesn’t even HAVE a seat. It’s like what you find in a hospital, they’re designed to basically flush a cornish game hen in 1 second.

Your 1.6L swirly home toilet doesn’t do the same, you can use a laser level to see for yourself. If the swirl is turbulent it’ll spray some, but lots of toilets don’t really emit mist much at all.