Rising sea levels due to AGW is a contributing factor[0]. Living in an area (whose economy is) also dominated by the oil industry, I understand why you and the people living in your area tend to be confused on this.
> they were able to calculate how rapidly sea level is rising with respect to the coastal wetland surface
Your link doesn't support your claim. It says region has a higher-than-average relative change. The sea doesn't rise locally, but the ground can sink downward locally.
You're being condescending. Everyone in the area knows that the main culprit in losing coastline isn't AGW but the taming of the river, essentially dumping sediment that used to build the delta over the continental shelf, and all the channels cut into the marsh.
My apologies, I didn't mean to be condescending. However, It is a fact that sea level rise is a large factor in this, even if it is not the "main culprit". Most people in that area rely on the oil industry either directly through employment or indirectly through the local economy so they tend to have a blind spot when it comes to AGW, which is completely understandable.
If sea level rise were a seriously contributing factor to the Louisiana coastline problem then other Gulf coast states with similar topography (Alabama, Florida, Mississippi and Texas) would have a similar emergency. As far as I can tell, they don't to the same extent. How would you explain that sea level rise affects Louisiana more than other Gulf coast states?
Every one of those states you listed are experiencing increased coastal flooding thanks to climate change and yes that flooding damages marshlands.[0]
Nowhere have I claimed that the issue in LA is solely AGW.. only that the sizable portion of the problem that is caused by AGW is going to fall on deaf ears in that region because of the amount of oil money there.
Having lived in the area, I will attest that a significant number of locals definitely have a blind spot about oil's contribution to AGW. However, AGW is not their primary problem, nor is it something they can do much about (yes, there are things they can do, and some do them). But they, and only they, can move their local dirt around, so they're doing what they the can do.
[0]https://www.sciencedaily.com/releases/2017/03/170314081553.h...
EDIT: added source link