The simplest way to put it is that Potentials have more energy available to them. The Dragons did...something in their sacrifice that altered the way human souls function (ish, maybe?) to create Foci and linked humanity up to a reservoir of energy that essentially powers Practice. Humanity in general was also changed and are still linked to the result of the Dragon's sacrifice, but non-Potentials don't get enough energy on their own to do much of anything on their own. Communal effort had been shown to be able to do things even before the Second Battle of Sol, albeit that it was rather limited, but it was that battle where the scale of what communal Practice could do started to become more apparent.
What's happened to Mary appears to be more like communal action rather than her Awakening as a Potential, given how that second one is typically very obvious. Due to who and what she is, humanity started to associate her with science, knowledge and discovery in a similar way that they associate healing, protection and leadership with Amanda. Neither of these lists are exhaustive, btw. As a result of this association, infrastructure slowly grew around her soul to support it, and then started, well, supporting it.
It's closer to being an Artefact than a Potential, honestly,
