I've added those into some of my own showers, not out of tile (which to me is risky) but out of marble or travertine and were much thicker.
I agree with the others that it is not much different than falling into the valve handle.
If falling were a concern such that that tile was a concern, no recommendation for replacement would be acceptable without a recommendation for a proper handicapped style, size, and located, grab bar (i.e., don't use a towel bar or a soap dish holder).
Not going to install a proper grab bar? I wouldn't worry about that tile. (Except that the thin tile with its unfinished edge looks el cheapo.)
It's soap dish / shampoo / conditioner shelf.
What about the shower head? If you fall and flail your arms around trying to grab something, you might hurt yourself on the shower head.
