This is my view for sure.I feel how on-foot was developed in Odyssey was badly thought out. It instantly disenfranchised those commanders who spent most of their time exploring outside the bubble, leaving them with an afterthought of a xenobiology mini-game, and no Artemis suit in a 2,000 light-year radius. Introducing ship interiors as part of the expansion would have likely been far more successful, and certainly in keeping with the continuity of game play as you suggest.
Still, bolting on a FPS was probably the least resource intensive option, which I expect is the reason we got that.
FPS can also be marketed to draw in New players whereas interiors is more for existing players.