Wasn't the non-browser nautilus mode chosen as a default for
accessibility purposes, either upstream or in Fedora or wherever?
yes and I pointed out why
the other mode was made so that one can drag and drop things easily
and if you have 10000000000s windows on your desktop
then you use shift double click
my suggestion was in the first place that solves both is
1. provide a patch that make shift-double click opens in a new window
2. upstream the patch
3. make browser mode to be the default because the usability issue is solved