Please recommend a small digital camera under $600 with an optical viewfinder. I have yet to be able to find one.
By small, I mean approximately no larger than two original iPhones stacked one on top of the other.
The optical viewfinder could technically be digital, but it must be usable while focusing your eye at infinity, like with an optical viewfinder.
If possible, please indicate if the camera has dioptre (diopter) adjustment built into the viewfinder.
(Questions regarding camera recommendations have previously been deemed on-topic.)