Acidic environment accelerate rusting because of the following equilibrium reaction:
Fe (s) + 2H+ (aq) <--> Fe2+(aq) + H2 (g)
Applying Le Chatelier’s principle, an increase in acidity, which is H+ ions, would cause the equilibrium to shift to the right. This would lead to a faster corrosion of the iron.
But i too have seen diffferent ways of it being explained, i guess you should just stick to wha you're most comfortable with
Leeching can be used to clean/stabilise artefacts. It takes a long time to work though.