Except they did it on purpose, which is why it's pretty obvious that it wasn't just an oversight on their part, so no need to 'worry' about our, "rationalizing the shortcomings," we'll be fine.
Doing it on purpose doesn't mean it's not shortsighted friend. There are better ways to do this within the code that they already have, I'm simply wondering why they didn't. For that matter, I'm wondering why are you opposing a new option that would take zero effort to change, reduce your options in no way, and add a few more options for everyone else?
Did you consider that you could also give your spouse simple instructions if they were a follower? Like ask them to wait for you somewhere? Or did you consider that you can give them stuff, like jewelry, weapons, armor etc if they were followers? There are lots of ways to use the follower functionality to pretty much double what you can do with an ordinary spouse.
I cannot see any rational reason for opposing the idea.