Hrm.
The Maldives at least should be fine. They are coral atolls which always lie at sea level, regardless of what height the ocean has been in the past (coral grows).
Wikipedia says satellites show a rate of 3.3mm per year. There's no evidence at present of an accelerating trend. So, 33cm in a century.
NOAA says:
"growth rates of 0.3 to 2 centimeters per year for massive corals, and up to 10 centimeters per year for branching corals"
Maldives should be fine.
Louisiana could have trouble, especially since it has already been losing land. Loss of sediment from upstream, destruction of the delta.
Although delta systems themselves, assuming nothing else is screwing with them, also tend to lie at sea level. The problem ofc is if massive immovable structures are built on them. I guess that's similar to people who build on barrier islands made of sand.
I suppose New Orleans could just a bit higher levees, since they have them in place anyway.