That all depends on what you are looking for in your Civ experience.
If I don’t want it on rails, then it won’t be.
Fair. I don't want it on rails either. Does it really look and sound to you like VII will be "on rails" though?
If you'll forgive me for the tangent, and the rather long post, I have many thoughts and had fun thinking this through, feel free to ignore me. I do get back to switching in the end, I promise.
In VI, your rails are the turn timer, tech tree, and civics tree. There is no going backwards or sideways here, only forwards.
As you progress, you have choices about what you do. In the early-game (generally accepted to be pre-feudalism?), these choices are primarily about where to scout, where (and how aggressively) to settle, what to build, and how to deal with your neighbours (incl. barbs and city states). These are mostly exciting and interesting choices, in my opinion it is the best part of the game.
In the mid-game, your choices change slightly. There is a second wave of settling, but a lot of this part of the game is about building the infrastructure you need. Beyond where to settle, choices tend to be around government policies, which districts you need and where to put them, pursuing critical great people or critical wonders, and what to do with your neighbours now. Generally, the focus shifts from early exploration to building the empire that you want, whether that be peacefully or through conquest.
In the end-game, none of your choices matter.
The sandbox side of it, as far as I can tell, comes down to how much you want to role play or mess around vs plot the optimal route through each stage of the game. It's about the narrative, and the stories you tell yourself along the way. You're still tied to the rails of the turn timer, tech tree, and civics tree, but you're free to beeline specific wonders or strategies that contribute to your story, as you wish.
I can't see any reason to believe that this will be different in VII, what am I missing? The rails remain the same; turn timer, tech tree, civics tree, with only forward momentum possible.
They've replaced the loosely defined early/mid/late-game phases with the three Ages; this is undeniably more structured, since everyone must do these Ages together, and there is no accelerating over the rails like a steam train whilst everyone else is still using horses. There are also now three tech and civics trees, and if you fall too far behind in one Age, you'll be back to the beginning with everyone else at the start of the next. This is certainly different, but you are still tied to going forwards through these trees, tied to the same rails.
Does this structure impact the choices that you can make along the way? The choices you'll be making in Antiquity are going to be very similar to the early-game choices of VI, aren't they? As for the later Ages, we don't know yet, but it seems to me that their is potential for a more diverse range of choices than the linear path of VI allows, with the added benefit that perhaps your end-game choices
will matter.
I can think of some specific gameplay things that you won't be able to do, such as focus everything on circumnavigating the world before everyone else, but I can't think of many. And you've got to think that, whilst some choices will be gone, and others changed, there will be new choices to make in VII. I recognise, for example, that the Ages structure most likely eliminates the winning in 38 turns shenanigans of VI, but that's more about hyper-optimal play with perfect conditions, not a sandbox in the slightest.
And then we get back to switching. As we understand it, you are
forced to change. We have an unavoidable crisis at the end of each Age that precipitates this change, but from a gameplay perspective, isn't this just another (hopefully interesting) choice to make?
I think the issue a lot of people have is not with the gameplay mechanics but that the narrative is forced. I'm not sure this is different to past games either, though:
- In VI, the narrative is that your civilization WILL stand the test of time, unless you lose. You can roleplay within that, based on the choices you make, but the overarching narrative never changes.
- In VII, the narrative is that your civilization will NOT stand the test of time, but your empire will, unless you lose. You can roleplay within that, based on the choices you make, but the overarching narrative never changes.
We can debate whether empire is the right word but it doesn't really matter which word you choose. I simply mean that your position on and influence over the map remains constant throughout the course of the game, unless you lose. For me, the core concept of Civ VII therefore remains the same as past games in the series. For others, this change of overarching narrative is too much, but I'm not convinced the game will feel like it is "on rails" as a result of this change.