The article doesn’t mention the well documented Dalton Minimum, forty years of low sunspot count and lower global temperatures from 1790 until 1830.
These minimums are apparently a normal part of the Sun’s cycle.
We have historical evidence of the solar cycles that produces minimums and periods of cold. The young lady has a hypothesis for how those cycles occur and a model that is prescriptive for an approaching period of cold that many of us will live to experience first hand. If she is correct, we face a coming period of famine when we can't produce sufficient food for the present population. The major Chinese dynasties have all failed coincident with such minimima.