You understand that the earth is neither a sphere, nor a perfect ellipsoid, yes? And that the earth has areas of more and less density?
Well those areas protruding out further from the center as well as those areas of higher density slightly distort the local strength of the gravitational field and direction in a minute amount, which alters the surface of the water.
The “level that water seeks” is the level where gravitational attraction to the water by the planet is equal, which is not completely smooth, due to the above factors (beyond just the earth spinning).
It’s not much, but it is measurable. It is also not something which changes rapidly, and is not what the posted article refers to.
Here is a map of the differences in gravitational strength:
https://earthobservatory.nasa.gov/features/GRACE/page3.php
The rises from the flow of ocean currents are a larger source of distortions, but together then can reach a couple of feet of variation.
All of that is basic physics too, just with a bit more detail.
After further reading on this subject, yes I do. What you are saying is that there may be a rise in ocean height more in one location of the globe than in another location on the globe.
I will accept that but then add, where is all the water going to come from to raise the ocean levels to the anticipated heights stated in the article?
My answer is, it ain't going to happen based on my prior post.
you forgot the effect the moon has on the tidal forces