Why are you hating on the black goo? The black goo itself is very mysterious. Nobody knows its origin. The Engineers are mysterious. Nobody knows their origin either. How are those 2 things combined less mysterious than the Space Jockey? They still leave a lot to imagine.
Well, everybody sure always wondered about what the Space Jockeys and the Aliens were and how they came to be or why the ship was carrying those eggs in the first place. Like I said, the black goo and the Engineers are not fully explained and still mysterious. The creation of the Alien in Covenant is quite interesting to me. It's basically a product of the human race's hubris and attempt at playing god - their unwary cration of sentient artifical intelligence / cyborgs (David) who turns kinda evil and - through a series of unfortunate events - gets the chance to create "something" in return himself. His "ingreadients" are basically the black goo (mysterious dna altering substance, not fully understood by anyone), engineer dna (who themselves are a the peak of biological evolution) and human (imperfect) dna, and David's own fucked up thoughts about what this new lifeform should be. All of that creates something beyond anyone's imagination - something really bad and terrifying. Like I said, the origin of all of this misery is "the human race's hubris and attempt at playing god" - personified in Weyland Yutani who created David. I think it's immensely cool and quite poetic that the Alien (which in the original movies is a force of horror to humans that both, internally and externally, kills them) is actually a product of humanity's own greed, carlessness, naivity and hubris - which has the potential the kill them all. Greed, carlessness, naivity and hubris are exactly the fundamental traits of how the Weyland Yutani Corporation has always been protrait in the first 3 Alien movies. Am I the only one who thinks the whole Prometheus and Covenant origin story is exeptionally brillant origina story for both the Aliens AND the Weyland Corporation once you've actually put some thought into it?