I think GP is pointing out that the ability to command a following or convince people to follow in your footsteps does not a genius make.

Brenton Harrison Tarrant commands a following and influenced a lot of copycats (his most recent disciple being the perpetrator of a certain shooting in Buffalo). So... can we categorize Tarrant as a genius purely on his influence of [others] that follow him?

As much as I hate to trigger Godwin’s law here, but that is equivalent to saying Hitler was a problematic artist …