Why do you think Apple chose the 4:3 aspect ratio instead of the more common 16:10/9 aspect ratio or other ones?
Is it because it is closer to 297mm : 210mm (A4 - ISO 216 - 297/210=1.4143, 4/3=1.3333, 16/10=1.6, 16/9=1.7778)?
Or is it easier to handle that way?
It looks slightly odd that way, but that may just be due to accustoming to 16:10/9 nowadays.
Is it because it is closer to 297mm : 210mm (A4 - ISO 216 - 297/210=1.4143, 4/3=1.3333, 16/10=1.6, 16/9=1.7778)?
Or is it easier to handle that way?
It looks slightly odd that way, but that may just be due to accustoming to 16:10/9 nowadays.
Theres already a thread about this....
https://forums.macrumors.com/threads/855209/