Civ VI isn't a bad Game, that's for sure. Actually it's a pretty neat Game considering how much Time we have put into it and how it keeps us engaged dispite its flaws. But that's not the Topic.
The Topic is, why the Game didn't even get close to its Potential? why are there so many obvious Bugs/Issue that are ignored? and will this be the same case in the next Iterations?
Vanilla Civ VI on release was a really solid Game, with many Bugs, but that's not unusual at releases. It got some decent small DLCs, but RnF didn't improve the Game as much as expected from an Expansion, whereas GS was a great XP (including RnF Mechanisms in the XP2 was a good choice from the Devs), but same as with RnF, the New Mechanisms never got properly connected with the Base Game Mechanisms. Which makes them feel just like something that's ... there. But that's not surprising since a lot of base game mechanics aren't interconnected with each other. The Game is still fun though, but not what a lot of us expect from a Game that evolved from many iterations, which gets me to the next Point:
Civilization is a Franchise that started over 20 Years ago, with Civ 1 succeeding even because it had a very small niche customer base. And looking back at all the Iterations, one expects that the latest Iteration to be the best one of the Franchise, because: 1) better Computer Technology with time that can improve the performance/complexity/appearance of a Game (including AI), 2) improving upon previous iterations, and 3) a Fan base that's already established to get Feedback from (be it Ideas, Opinions or Bug Reports).
But despite that, People are constantly saying that they find previous iteration are better (especially Civ IV). And FXS Philosophy of "keep a 1/3, change a 1/3 and drop the rest" is the exact reason for that IMO. I'm not saying that the Game should be the same as a previous titles but with more features, but droping good mechanisms that could just be improved, just because of a Philosophy that has worked for the first titles, is a waste (eg, Civ V's Social Policies or Civ IV's Vassalization mechanisms). It's good and essential for a Game to introduce new Features, and the Civ Franchise has constantly delivered great new content, but dropping good features just for the sake of introducing new ones is not a good approach.
And that's why Civ VI was received very positively by the Fans at release (lots of Civ V features that got improved), but the Expansions not so much (GS's mechanisms are good but not properly integrated into the Game (and we still suffer from the Disasters, that are maybe the reason of all the Asset/Map size limits!!)).
The Developpement Philosophy that I think Firaxis should follow instead, is: Keep everything that works great and maybe change them a bit based on the new features (Alt Leaders, Unique Abilities, Natural/World Wonders...), improve the things that are good ideas/concept that could be (much) better (Citizens, Amenities, Loyalty, Eurikas/Inspirations, Governments ...), rethink and redesign everything that isn't good or cannot be improved directly (Civics Tree, World Congress, Diplomacy ...) and drop everything that didn't work. And in regard to new content: make sure that they are well designed and interconnected with some of existing content (great Job from the Devs when they made some Districts Unique to some Civs).
That never worked for any of game companies. Look at pokemon. They are not listening to hard core gamers and are keen on making game lite and accessible to casual gamers-even removing Battle Frontiers.
Look at how well civ 6 has sold.
In the end it all comes down to $$$$. Especially in capitalist society.
That's not always true.
As an example, look at Eric Barone who got so dissapointed from how badly "Harvest Moon" (a game that he liked to play) evolved (similar to the Pokemon Games), that he decided to make its own version of the Game. 4.5 years later he released "Stardew Valley" (2016, the same year Civ VI got released) and on january 2020 the game sold over 10 Million Copies, whereas Civ VI sold ONLY 5.5 Million Copies as on August 2019. Nearly double the amount of a Game that's developed by a TEAM of professional Devs with many Years of Game developpement experience and from a Studio that has released many iterations of the same Game (I'm not speeking low of the Civ Devs here. I know a lot of them, if not all, want to make the dream Civ Game we all want to play, but the higher-ups might have another Vision) !! A game made by ONE SINGLE PERSON!! And the Game is still being a hit, and Eric is regularly updating the Game, fixes Bugs (without having to make purchasable DLCs in order to fund the BugFixes), and adds new features
FOR FREE. and he makes sure that the game is modding friendly.
Why? because he made it with love, carefully, took his time, and was constantly in touch with his community.
I know it's a different Game, and not comparable to Civ's 4X genre that needs a good AI and complex Strategies, but nevertheless, I'm sure the Amount of resources that FXS has spent in the Game could have easily made a much greater game than Civ VI.
But tbh, I don't think the Franchise will
ever make the game we all want to play. why? because Stardew valley was a one title hit. a Second iteration of it wouldn't be half as much as successful (that's why Eric is now also working on another Game). And look at Henry Ford who made robust Cars that should last for a living, and then General Motors suddenly closed its Automobile factories, because they made Cars for everyone who could afford it. Till they brought the same cars to the market but with different Colours, so they can still produce and make money. Yeah, that's the same Strategy that's used by fashion companies: every Year/Season there is a new Style to make more money from.
And that's why I think Civ will always inroduce different games, but similar enough to recognize it as a CIV Game. (something I neither like nor dislike tbh)