EDIT: Found a solution to this. My landscape somehow got resized to a small increment and I never noticed (100.000001% scale). Probably because it is not possible to make objects non-selectible from the viewport and I dragged it without noticing (grr, epic plz).
Anyways after resetting the landscape scale to an integer value the gaps are gone. Hope this helps someone else out there, and epic please make objects non-selectible in the outline for god’s sake it’s 2022