I was saying something about X4 in another thread recently regarding the on foot portion, but I feel like it does add something, at least for me. Egosoft started down that path with X Rebirth and it was pretty bad, and it seems like what is in X4 is mostly just a cleaned up version of that and they didn’t try to add any more and attempt any FPS type gameplay because it almost certainly would have sucked.
But what it does is give a really cool sense of scale, being able to hop out of your ship on a giant landing platform and see a line of some of your other ships docked there, smaller ships buzzing about, even watch ships get built and take off. It isn’t forced on you much at all other than to go talk to NPCs for quests, and otherwise is just a nice little bonus.