There's a whole lot of related suggestions here for sorting that mostly revolve around cleaning up duplicate / large tab lists.

Sort folders alphabetically

Sort tabs in windows

Option to sort last opened urls

Make it easier to edit/delete

(Sadly userecho won't let the community self-organize and propose merges to duplicate suggestions...)

Even without automated duplicate removal, sorting the lists (either globally, or by Group/Window/...etc) would be a key step to enable folks to clean up their own lists. Please consider.