What meaning of conservative? Because the deep south has that affectation too. Everyone is mister or Mrs or Mz (my favorite by far). When talking to a child about someone it's Mr. Given Name. In polite company when discussing a non-mutual acquaintance of some regard, it might revert to Mrs. Surname.
I am also constantly called sir and I cannot say "ma'am" like the people out here so I don't bother with that frivolity. They also say "no" with extra vowels that are somewhat silent, like noueh, it ends more in the nose than a normal "no"
Conservative in the meaning of not changing lightly. Conserving the current state (which for English style in the New Yorker is now rather old style, but why change?)
The examples you give are not written media. If you look at newspapers in the deep south, I'm willing to bet that they're not referring to people as "Mr" and "Mrs" (and a quick check seems to confirm this).
Secondly, the NYT is not in the deep south and doesn't abide by local conventions, so it stands out relative to its peers (e.g. LA Times, etc.).
I am also constantly called sir and I cannot say "ma'am" like the people out here so I don't bother with that frivolity. They also say "no" with extra vowels that are somewhat silent, like noueh, it ends more in the nose than a normal "no"
So that's the link I drew.