The question, for me, is whether the game design gives you the real, or at least semi-historical, alternatives when it requires you to make a decision, and Civ V in its basic design made the decision to show no negative sides to your decisions at all. Basically, your every decision is between two (or more) Positives, and you are only deciding which Yellow Brick Road you want to follow, or follow first.
A better game, and this is just my opinion, would be one in which you have to make decisions constantly, and some of those decisions will include negative outcomes, which you will have to compensate for in other ways. Even such nastiness as Addiction (Tobacco, Alcohol, Coffee as Trade Goods or 'Luxury' Goods) and Slavery should be included because they and their consequences were a huge part of history, and a supposedly-historically-based game should include them in some form.
In fact, although I am NOT advocating making Civ VI into a Teaching Tool, by including both the positives and negatives of historical decisions, you can teach a gamer a few lessons...
For example, Slavery at first glance looks like a source of Cheap Labor (Workers) BUT, as historical groups as different as Virginians in 1840 and Spartans in -300 could tell you, a large slave (Helot) labor force also requires a large Security Apparatus to keep them working. Cheapening labor and making it the province of slaves also stifles initiative and innovation among the rest of the population - try to find a technological or philosophical innovation that came out of either Sparta or the American South. The way to show that in the game might be to include a constant % chance of Slave Revolts in your slave-holding cities AND the 'slave' population points in your Civ could not be applied as Specialists of any kind. Cheap Labor with an extra Price.
Along similar lines, I think there should be a lot more conflicts among the various Social and Religious Policies - there are combinations of, for instance, Freedom with Piety, Honor or Tradition policies that should trigger conflict among some of your citizens, yet right now you can 'cherry-pick' any combination of Social Policies in the game and apply nothing but Bonuses from them. This is Sanitized History, or Historical Fantasy if you will...