Let me try to make a bit of a contrarian case:
Laws should encode 'reasonable expectations' that humans have of each other in society. Those expectations shift over time.
Is it a reasonable expectation that a marriage includes somewhat regular sex?
The modern equivalent of the Clapham omnibus (ie the normal person's reasonable expectation) might be something like the MN AIBU boards. Where living in a sexless relationship against one's will is widely considered grounds for splitting up. That's not seen as an old-fashioned view on AIBU.
I wouldn't have drafted France's laws like that, but it's not based on archaic mores and (as far as I can tell from Google) not asymmetrical. It's just AIBU but codified.
(Not to be confused with permitting of marital rape, illegal in France since 1994).