This is not unique to this product. The issue on the dangers of silica dust is well known, and long standing. Any sort of dry cutting or grinding of concrete or products made from it creates the exact same hazard. Proper respiratory protection, or alternative methods such as wet-cutting that do not create the dust hazard, are required. It may be that we’ve all seen contractors grinding away in a fog of this dust, but it is strictly regulated by OSHA.
Cementitious fireproofing bags also have this silicosis warning on them.
I have worked with Hardie board siding on my own house and it is rather nasty. Very fine powder dust and it smelled of burnt material.