I have an appropriate stool, and have used and compared it over a lengthy period. The subjective benefit over time is not 90%; it is about 30%. When squatting, there is no risk of falling if one has normal balance and is not unwell. It is not for the inattentive person. It takes weeks or months of use to realize its pelvic benefits.

The risk of falling is highest when getting off the seat, at which time it helps to have a support to hold.

The correct solution would of course be to remove this toilet altogether, replacing it with a squat toilet.