Out here in SoCal the main failure point for GE luminaires in HPS was the ignitors on units manufactured in the 1990s, particularly the plug-in type. Cap failure was very rare for most generations.
I wholeheartedly agree with AE peaking under ITT. Every parent company beyond that started cost cutting the build quality. 113s for example looked good brand new, but seemingly aged poorly.
Can’t say much about Cooper since they were rarely used.