But why do we want more permanent bonuses?
Well, I suppose I can elaborate on my "if Civ's gonna keep pushing the completely parallel playstyles", because I don't take it for a given that this is a good thing for the game's design, but I do take it for a given that it will continue to happen. Civilization VI leans heavily into having the different VCs effectively be a different game. They all interact with some mechanics, but most mechanics in the game are not really focused on for more than 1 or 2. The idea being that by about the mid-game there will be multiple vectors of strength at which various Civs excel, and allowing players to have very different game experiences between runs. This makes the game very....sandboxy, for lack of a better term, Civ VI is like a complex set of Lego blocks you can mix and match for as many interesting combinations as your imagination permits, focusing on the "final result" with very few external pressures. This is also why I don't think the game is going to get any harder, because that sandbox element has proven highly successful with a large segment of the market. To reiterate my previous point then, if Firaxis is going to continue in a sandbox direction for the franchise, giving the players more toys to play with only makes sense.
Civilizations, empires, and peoples change over time and adapt to their circumstances. If your neighbors are aggressive, then you devote more resources into military matters. If you have peaceful neighbors, then perhaps you look into culture or science. If you acquire coastal territory, then you might devote some time to learning more about exploiting that terrain. And so on. Permanent bonuses are actually kind of boring.
The contextual focus of of civilizations historically is arguably covered by other, more direct player actions: If you're feeling military pressure, build units. if you feel you need more science and culture, build the appropriate buildings, promote/upgrade pingala, get a wonder or religious bonus that helps. If you settle some coastline, you'll probably research sailing, maybe build some boats. This doesn't really need to be represented by policies, and especially the way that Civ VI does that makes no historical sense: "Want to make some improvements to your land, better adopt Feudalism for 2 turns. Builders done? Great, get rid of that, no problem. Need more 10 turns later. Back to Feudalism we go boys!" "I want my people to get a Pantheon, better have the worship me as a God for 25 turns until they discover....other....dieties.....don't question it." "My people have spent most of their early history in way with the Aztecs, but by adopting an Oligarchic and militaristic social structure we have been able to conquer our enemies. But, we're about to finish our Ancestral Hall, so we must become a Republic for a handful of turns to grab the Legacy card. Either way, I'm gonna go to Monarchy in a dozen turns anyway." My point here shouldn't be confused as saying that V's Social Policies were any more realistic, but rather that I think Civ is fundamentally unrealistic in how much freedom it gives the player to sculpt their Civilization, and I don't think that's going away.
Permanent bonuses being boring however, that's something I'd like to hear you elaborate on if you're willing, cause I find with VI that just the opposite is true. Social Policy cards suck because there's no consequence to just quickly swapping Feudalism in and out, or military production, or wall production. Being able to specialize in whatever I'm currently doing means I am effectively specialized at doing everything, at which point there's little function in specialization at all. Social Policies at least allowed the player to mix and match different synergies, and the fact that they were permanent meant that your decisions had opportunity cost, and consequently strategic weight. In Civ VI even the more extreme Dark Age cards tend to be used with little consequence, because if the downside's going to cause a problem you simply switch them out. Laws systems like in Civ IV and Old World provide some middle ground here, although the latter leans too far towards Civ VI's impermanence for my liking, and Old World's laws only make balancing sense as one of many ways to spend a powerful secondary resource (Civics)
NB I'm not saying the Cossack Hetmanate doesn't deserve to be in the game; it would just be far less interesting to me than any of Bulgaria, Croatia, Serbia, Czechia, Romania/Transylvania/Wallachia, Lithuania, etc.
Probably other scenarios too.
