Modern desktop OSes like MacOs will dynamically fill up memory to improve performance, since unused memory is wasted memory. And will leave things in memory for as long as possible until something else needs it, then that occupied memory gets freed by pushing a chunk of memory into the swap disk. It’s why if you run MacOs for while the memory gets full, even if you don’t have anything open. But that memory will get freed if you open an application.
Modern desktop OSes like MacOs will dynamically fill up memory to improve performance, since unused memory is wasted memory. And will leave things in memory for as long as possible until something else needs it, then that occupied memory gets freed by pushing a chunk of memory into the swap disk. It’s why if you run MacOs for while the memory gets full, even if you don’t have anything open. But that memory will get freed if you open an application.