Salah is the more effective goalscorer in a team that is built to maximize his effectiveness. For Egypt when the onus is on him to carry the team he can't as he doesn't have the skillset to do so, and is reliant on his poorer teammates to create chances for him.
Hazard is the more talented footballer who played in mostly defensive counter attacking teams where the gameplan was usually 'pass to Hazard and pray'. Domestically he was fantastic but lacklustre in Europe overall. For Belgium KdB was better up until about 2015 where Hazard took over and was their best player consistently. Also the best player in the 2018 WC.
Effectiveness should only trump talent if said talented player doesn't win the honours (individually and as a team) that his talent suggests he should. In this case Hazard won multiple league titles and also multiple PoTYs which puts him above Salah. No one in their right mind would rank Lampard above Zidane because he statistically betters him. They both won everything there is to win so who was actually the better footballer should prevail.
Salah in Liverpool is 100 times more dangerous than Salah in Egypt and it’s not hard to imagine why. Liverpool play in a kind of way that make it difficult for opposition such that if you focus on Salah and take your eyes off others like TAA, Robertson, Jota, etc you’ll get hurt.
Liverpool is a chance creation machine that keeps coming at you from all directions so Salah can pick his moments cleverly and get a good chance and then hurt you when you loose a bit of concentration because of everything that is going on around. And boy, Salah is good at maximizing these half chances - maybe the best in the world. But if you look at a team like Egypt, once Salah is closed down, because there’s not much happening elsewhere on the pitch, there is no danger at all.
The last AFCON where South Africa won Egypt it was the same story as yesterday as Nigeria marked out Salah out of the game. Hazard on the other hand was very difficult to be caged and while his numbers underwhelmed, his general play was almost always top notch. Football is so dynamic that it’s hard to make these sort of comparisons.
I still think there is some recency bias and over reliance on numbers in judging the two players but with that said, with the way Salah is going this season, I can easily rate him over Hazard.