I thought it was interesting when outdoor kitchens started showing up a few years ago in new campers as if it were a novel innovation. I have added an outdoor stove to every camper I have ever owned and I carry an outdoor kitchen normally used by tent campers. After all, you go camping to be OUTDOORS.
While I like the new outdoor kitchens, I also like small travel trailers that allow me to go more places. Small trailers just don't have enough space for two kitchens, so I make my own outdoor kitchen.
Nearly every camper made since 1995 has an outdoor propane connection. If not, it's easy to add one. So it's easy to add a portable stove and/or grill. Then you can bring an extra ice chest or small refrigerator, which are quite cheap. You can even buy a portable ice maker for a reasonable price. A jug of water and dishpan have always served as a sink, but obviously less convenient.
So my opinion is that an outdoor kitchen is essential for enjoying camping. If your RV can accommodate one, that's great. If not, make one using the equipment that tent campers have always used.