> Racism and/or vote fixing via the methodology claimed in this article would be a serious and despicable thing, however, as far as I'm aware, we are protected from this now and have been for a long time.
The protection took a major hit in 2013, when the US Supreme court made a 5-4 decision in Shelby vs. Holder [0], permitting some areas to (re-)start a strategy of imposing unconstitutional and discriminatory laws just before an election, with local authorities knowing that any court-case voiding their law can't arrive in time to matter. Then they just enact the same kind of discriminatory law before the next major election, over and over, with no real punishment.
While state legislatures aren't currently choosing to enact things quite as blatant as before, the same exploit makes it possible.