Who wants these calls? It ends up that the people that don't know that these lists exist (my grandma) still receive these calls - so everyone who's likely to be baited in buying something they don't need for way too much money.

Also, it depends on the company keeping their word that they won't call you when you are on this list.

Nobody needs or wants these calls, they are always some company wanting to upsell you something you don't really need, they shouldn't be opt-out.