I know it sounds cynical but I don't think such a simulation tool would make any difference to convince the general public.
As a thought experiment, imagine if we had a computer simulation in the spirit of Conway's Game of Life[1] or Schelling's Segregation Model[2] to simulate the spread of viruses and breakdown of herd immunity when you have anti-vaccination parents. Showing that "evidence" to anti-vaxxers isn't going to change their minds because they distrust the "government" and "scientists". (E.g. "And who created that simulation?!? The government scientists who want to make our kids autistic!")
Same situation with Brexit. The big multinational companies favor the EU but the "little guy" sees his job getting threatened by immigrants. Asking everyday people to be scientific and weigh the "big picture" instead of being emotional about their immediate livelihoods isn't realistic.