My older cat, Onyx, loves to watch outside, and before we moved to a big city into an apartment, we were living in the midwest in a house. We used to let onyx out, (on leash) to hang out in the backyard since he would always stare out the window. Just like you, we felt like he is missing something....he didn't last 20 minutes outside, before sneaking back into the house. We tried it at least a dozen times, putting him on a leash when we were having a drink outside...he would always sneak back in. So no, only because your cat is staring out the window, doesn't mean he will like it there more. Maybe he is thinking to himself how the outside must suck.