Why? The natural “up” direction is north, and east goes great with it like that’s where the sun comes up and also arrows pointing to N and E look like the coordinate axes in a default oriented graph.
https://www.ancient-hebrew.org/philosophy/east-time-eternity...
One of the interesting implications is how they view the past as east and the future as west (or conversely, the past as in front of you and the future as behind you). I'm not precisely sure I yet understand why this is, but I wonder if it's a matter of visibility? e.g., we can "see" the past but not the future.