So if I have a red taillight installed on my bike that makes it impossible to install a reflector, then it's OK, seems? (above underlined part)
I would read it as, if you have a red taillight that makes it impossible to install a reflector, you need a different taillight. The standard that you need a taillight does not conflict with the requirement that you need some sort of reflective material. The underlined part of section (e) means that when the commissioner makes whatever rules he chooses to make, those rules don't trump sections (a) and (d).
If section (a) says you need a belt, and section (e) says you need suspenders, you need a belt and suspenders.