Shavua tov Daniela. Thank you for the kind blessing. Never despair of ignorance. It has an excellent cure rate.
The primary reason for not using salt in matzo is that it renders the matzo Matzo Ashisra, or “fancy bread” and matzo must reflect lechem oni. Secondarily, anything whose effect were unknown were avoided in matzo.
I consider myself fortunate to have had a good science background, and to have lived in a time and society where science is held in esteem, as it functions as a handmaiden to Torah. I was also fortunate to cross paths with Rav Blumekranz ztk’l. In some of his older publications he listed the physical process of water+b amylase= starch to sugar conversion= native yeast nutrient+ gas and alcohol release trapped as bubbles in gluten=chametz. This process is stymied by salt, but that was maybe not recognize or accepted.
In halacha there is a mention of kimcha divshuna. This was flour made from roasted grains that was recognized as not subject to chametz. Of course, heat destroys the enzymes, and the yeasts.
It was forbidden a long time ago because of the risk of a non complete roast. Flour (cake meal) and meal made from matzo is used just in this way, and it cannot become hametz, unless you reintroduce a composite of enzyme and yeast. All this works until you say that chametz is only a spiritual thing.
I also found a Rashi recently that would seem he held kimcha divshuna was malt, and I have strong theory that the malting process is exclusive of the chametz process.