Both the repetition of the rules and the lack of intimacy make for a strange ending though. What is the conclusion ? That being married is the same as living together with a friend except you also promise to stay together ? The question isn't so much about us knowing they are in love (we know that) and more about why their love takes that particular shape.
Also, there is a pretty thin line, maybe even just a matter of point of view, between intimacy being unnecessary to show your characters are in love, and having to show your characters are in love within the constraint of not showing intimacy. Which I guess is why this kind of resolution reminds people of works from 30 years ago.
In the end, we know they are married, in love with each other, and they don't mind kissing - their relationship is not just for show and there is nothing inconclusive. I don't think there is an argument that the story didn't go all to way to its conclusion, or that their relationship isn't as genuine as any other you could think of. At the same time the last chapter, in which they make their wedding "official" in front of others, emphasizes physical distance (repeat of separate bedrooms and wedding without a kiss), which is a deliberate choice which, at least to me, feels a bit off-putting.