My knee jerk reaction to this was “Why build an island when the glaciers are melting and the global sea level is rising?” but then I looked into it and by 2100 the average rise will be about 0.3m. Just dredge up more mud and you should be good!
As the article states one of the functions of the island is actually to protect the rest of the land from rising sea levels because it will involve building advanced flooding protections.
(Also as a side note, a 0.3m rise doesn't sound like much, but that is an enormous mass of water. IIRC a rise of that level would destroy more than a quarter of the land of most American coastal cities)
It may be "putting at risk" - I can easily imagine that most seawalls aren't 1 foot above high water line but are designed with some safety in mind for storms and such, but now are at risk to smaller storms.
Yes, sue nature for 4 times more tidal range than the 0.3m cited due to climate change. If you can handle the tide, you should just need to allocate bit more space to shore.
(Also as a side note, a 0.3m rise doesn't sound like much, but that is an enormous mass of water. IIRC a rise of that level would destroy more than a quarter of the land of most American coastal cities)