There is one thing I don't understand about the article. The rise in groundwater level should follow the average increase in sea level. It is not like a big wave would suddenly affect the groundwater level.

Assuming houses last for 50 years and during the next 50 years the sealevel can increase by around 50cm, it should be easy to check if buildings near the coast are high enough that they can accept this change in sealevel.

Of course, damage done by flooding does depend on how big waves are. So you need levees and seawalls long before you get a groundwater problem.

That said, you don't want to pump fresh water out of the ground close to the sea (unless you inject at least as much fresh water). But that is independent of sealevel rising.

Finally, plenty of Dutch houses are built in swamps below sealevel. The technology exists.