Talc is perfectly safe in cosmetics, and it is one of the better ways to create powder cosmetic products.
The end result depends upon the whole formulation and not just on one ingredient. You can have inferior products or superior products, both using talc, just the same as you can with any other one ingredient.
Some of the highest-end eye shadows and face powders are talc-based -- Laura Mercier, Chanel, to name just one of many, many lines. Laura Mercier eye shadows are incredibly smooth, finely milled, and well-pigmented -- just about the best out there. Bobbi Brown Sheer pressed face powder has an amazing finish and texture -- yup, talc.
~Who in the world am I? Ah, that's the great puzzle~ Lewis Carroll, Alice in Wonderland