Horizon line and water made of squares

[SonicBoom1000]

Since the Update the general performance in single and multithreading are garbage I come from 160+ fps with almost everythin at max (RTX3070, i71400k, 64Go 6000Mhz Ram, SSD 4To) to something absolutely inacceptable.

But look at THIS : what are those awful squares ??? I never played the game rendering like this, as ugly, and unoptimized.