MacOs still cannot get full screen right

MacOS's full screen mode is infuriating even on its own native apps. It's always buggy and doesn't scale properly. Even with default display resolution - it consistently does not show full screen. Not sure if others have the same experience and what the solution it. Reboots usually help, and then reverts back. https://preview.redd.it/sqixpb98l1ie1.png?width=3600&format=png&auto=webp&s=91a72471da6b47dd88f4ce2f5024dc68276c700f