I’m don’t know any ultra-Orthodox but do have several friends/family that keep kosher, and all of them are satisfied with just keeping two sets of dishes (although some just have one set and are satisfied that washing them count).
The disposable dishes, cooking in foil, and such comes up when they visit someone like me who does not maintain a kosher kitchen (and even then, only one family actualy cares enough; but, as I said, they are not ultra Orthodox)
I’m don’t know any ultra-Orthodox but do have several friends/family that keep kosher, and all of them are satisfied with just keeping two sets of dishes (although some just have one set and are satisfied that washing them count).
The disposable dishes, cooking in foil, and such comes up when they visit someone like me who does not maintain a kosher kitchen (and even then, only one family actualy cares enough; but, as I said, they are not ultra Orthodox)