I Wonder how many buses are running around at night (or in the dark) with
non working blind lamps?

I can't think of the last time I saw a fully working lamp set. Most I've
seen/used have only the number illuminated which is fine if you know what
number bus you want rather then where it's going, or even a old school 'via'
point.

Don't garages VDI there buses before they go out on a turn or diagram
whichever its called in bus world ?

Which comes back to the point people have made before - nice yellow/orange
LED destination displays would solve that problem (and the 'via' problem)