The day that all of you Civvers have been hoping for is here. Firaxis have been promising Civilization 7's Test of Time update for a while now, and as I write these words into existence, that very update is available for you to download, complete with the most requested feature, the ability to play as one civ for a whole campaign.
This has been a particularly notable thorn for those who have been playing the Civilization series for a while now. With this update, as detailed in a blog post, that all changes. Now, any civ you decide to play as can be guided "outside its historical Apex Age," the point in time a civ is at its peak, essentially. At the point you'd normally perform an age transition, you can instead choose to carry it on, though the option to swap is still there too.
Civs that play outside of their apex age are now called Time-Tested, consisting of a twofold framework, civics and syncretism. Time-Tested civs get their own tree that includes one "truly unique" civic that is "crafted specifically for that civ in that Time-Tested Age, which provides Traditions and other effects that reinforce some of the civ’s feel in a way appropriate for that Age," a civic based on the civ's attributes, and then a new kind of civic that enables syncretism. This is apparently "the borrowing, affirmation, or integration of concepts, symbols, or practices of one tradition into another," which essentially lets you nab ideas from other civs to use for your own.
Beyond that, there are two other big additions with this update. There's Triumphs, which are replacing Legacy Paths. "Triumphs offer a wide range of optional challenges tied to the six core Attributes in Civ 7," explains the blog post, noting that there are minor triumphs that can provide instant benefits, and major triumphs that "require more focused investment in their associated systems and grant Dedications for your next Age." And then there's a revamp of Victories, which each have their own score you can rack up to accomplish them.
It's a big update with lots more changes besides those mentioned above, all of which you can read about here.