Aldehydes (pKa ~17-20) and ketones (pKa >20) are worse acids than alcohols (pKa ~15-16). I have seen that the equilibrium of aldehydes (and ketones) with their hydrates greatly decreases pKa values like in benzaldehyde which is comparable to alcohols.

Enols are in equilibrium with aldehydes too, and since there is resonance stabilization of the enolates, acidity should increase in the same way. Here it's given that alkenols are better acids than alcohols and I think concentration shouldn't have an effect as enol consumed by the base will just get replenished by the equilibrium shifting forward until all aldehyde is exhausted.

But that doesn't happen, enolate formation isn't favoured with aldehyde in RO-/ROH, why is that?

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