As a collector of things lost in time, such as Native American artifacts of which I have found thousands immediately around me in the last 15 years, I can say that erosion does have its benefits. Just as we are now reading from those exploring glaciers finding previous human tools and more. The word "benefit" here is clearly subjective.
For instance, Vanatu:
https://climateknowledgeportal.worldbank.org/sites/default/f...
There is nuisance flooding, which is definitely up already in many parts of the world, and then there is the kind of flooding that essentially makes it impossible to live in certain places. My own country (NL) has been working since a bad flood in 1953 to raise the various flood protection systems to account for rarer events and the mechanisms put in place have already been triggered several times. Right now they're working on raising the whole protection level another meter (three feet), and if necessary they'll do more than that but there are some complicating factors. At some point the rivers won't empty any more and you end up with either reverse flow or internal flooding simply because that river water has nowhere to go to.
Sea rise is not just about flooding, but it affects sewers and infrastructure well before affecting properties.
Extreme weather, in the other hand can affect big areas for extended amount of time, right now. In 2022 a third of Pakistan ended flooded, in 2024 there were big floods in parts of Europe and South America. Droughts, extended forest fires, tornadoes and similar has been changing in area patterns and strength in the last years. And things may get extremer in the coming years
A lot of areas won’t make sense to insure due to storm risk well before they’re at risk from literal sea level risk.
Not in an emergency scenario but more like "it doesn't make sense to stay here anymore".
I mean, I can tell you why. It's not feasible if it costs too much. If it makes sense (i.e. the land is worth X and cost of a wall is some fraction of X that people can afford) people will do it.