Ah, yes, “reasons”.
- Jedi use Ilum crystals, which only come in blue and green. Sith use synthetic crystals, which only come in red.
- Jedi sentinels use blue crystals while Jedi consulars use green.
- Kyber crystal colours reflect the affiliation/temperament of their users.
Blah blah blah bullshit.
Aesthetics and symbolism are the only valid reasons for any lightsaber colour.
How is it “bullshit”?