I agree with most of this. I'm light-skinned but I KNOW that light-skinned Black women are generally (not always, but mostly always) preferred to dark-skinned Black women by Black men, for various complex reasons.
Should they be jealous? - well, no one SHOULD be jealous of anyone - it's a negative emotion - but I have no doubt that some are and that's understandable, while others are not and are confident in themselves and what they have to offer.
Light or dark-skinned, we're all Black women and therefore all have to struggle and it works better if we come together to do it.
Get used to me. Black, confident, cocky; my name, not yours; my religion, not yours; my goals, my own; get used to me. -Muhammad Ali