If you look at the related questions, you can see that this question has been asked and answered multiple times and there has been no movement on this issue.
Changing it, even if there were consensus on doing so, would be a software feature request. There's already multiple things broken with the now hundreds-of-thousands of living unlisted profiles which should take priority. Software feature requests do require developer attention which is a limited resource.
There is already a trivial workaround for folks who find it important to have their spouse linked on their public profile: put a prominent link in the biography. Besides privacy issues, a much bigger missing feature I would consider is the limitation of linking a single profile to just a mother and a father; there's no semantic way to link a single profile to both biological and nonbiological parents. And one can link to two nonbiological same-sex parents, but only while creating the odd data-doctor issues of foisting a male "mother" or female "father."
That's why I'm saying this is not a battle I would personally be picking now. To be clear, I didn't mean you shouldn't have asked the question (although it has already been asked/answered before). I meant in my personal opinion it would not be the right time to try to push to change this.