I can't speak for the others but Fallout 4 certainly isn't empty. The amount of content is staggering and there is always somewhere to explore. Since I also run about 20 settlements, I can also say that I'm very attached to the world. It has plenty of touches that make it feel unique, too, like sneaking up on raiders and listening them tell crazy stories to one another (the one about the guy pretending to ride a motorcycle around the wasteland is hilarious) or stumbling on random encounters, like the two guys who look identical and both claim the other one is a synth.
They just aren't for everyone. You have to like to explore and find new situations, you have to like creating your own story in your head as you go. Some people like to go on a ride, to just strap themselves in and let the game take them down a path, and that's fine, but it's not inherently better. It's just different.
