Since the lift is generated even if the wing has a symmetrical profile, it seems to me that having a higher profile more curved than the lower profile is not the only characteristic at the base of the lift but serves to increase its efficiency.
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Summing up what I do not understand is what the difference in the air speed above and below the wing is due to. Rather than in the explanation by formulas I am more interested in a physical explanation (what pratically happens to the fluid).
See: https://aviation.stackexchange.com/questions/39146/how-do-symmetrical-airfoils-generate-lift and Bernoulli and Newton.
An oversimplified and short explanation is that the upper surface has a longer path whether the airfoil is symmetrical or not, that provides the lift. If the angle of attack was zero, like symmetrical rocket fins, there would be no lift; only straight travel, accounting for weight and force / vector.
