I sincerely hope that Tech Tree we have so far is not the final version, but I'm afraid it will be very close.
It looks very much like, having decided to move a lot of the 'technologies', Wonders, and some units to the Civics Tree, they lost interest in the Tech Tree and knocked it together on a Sunday morning while they were hung over - or still drunk. At the very least, it looks simple-minded, as if the 'Technologies' were invented to give something to hang Units, Improvements, and Wonders on. I mean, seriously, folks: technologies named 'Apprenticeship', 'Castles', and 'Square-rigging'? The formal Apprenticeship system was a product of Social change, not technology, the Castle was the Product of a Social/Political system that required defensive fortification to keep an eye on the source of wealth- land, and 'Square-rigging' is meaningless: the Bronze Age Galley had a Square Rigged Sail, for Cryin' out loud!
And, in too many places, the progression of the Technologies makes little sense, either Historically or for Gameplay purposes. Right at the start, Mining Tech gives you access to 3 other technologies, while Animal Husbandry only 2, and one of those an Era away, Pottery access to 2 technologies in the same Era, but presumes that Pottery was a requirement for Writing. Say What?
The requirement for Writing is the Necessity to Keep Records. So, yes, having a bunch of pots full of Stuff requires record-keeping, but so does having a bunch of valuable animals and their products (horn, hide, leather, etc) to keep track of. Writing is one Technology (among many) that cries out to have more than one antecedent, and the ability to be reached via more than one route.
The Wheel requires Mining, but not any animals to haul the wheeled vehicles. What are you mining here, Hubcaps? Without a domesticated draft animal, the Wheel may be invented, but it will not be
used - see the technology of the Americas for examples: there are toys using the wheel from Precolumbian Mexico, but no larger wheeled vehicles. The Wheel requires Animal Husbandry, and the 'Boost' should be at least one pasture: even a cart pulled by a goat/sheep will do, and obviously cattle (oxen) or horses are the classic Draft Animals.
I'm not going to go into the rest in detail, because it would take pages BUT there is one more thing: having come up with the Civics/Culture Tree, why didn't they integrate it more with the Tech Tree? Specifically, there are quite a number of military units that require certain Social developments rather than technologies. Just for example, the Hoplite is just another armored spearman, until you add the social concept that all the members of the group are equal citizens and the greatest disgrace is to Let Your Neighbor Down by breaking from the wall of shields - each of which protects the man on your left as well as yourself. Likewise, the Roman Legion was just a bunch of swordsmen until you added Military Training and a near-lifetime (20 - 25 year service commitment) in the Legion. The Knight was an armored horseman, not appreciably different from the late Roman heavy cavalry, Byzantine Cataphract, Sassanid Persian Clibanarii, Sarmatian armored cavalry - until you added Fuedalism and made him a Social critter, given land to support himself so that he was Always Ready for War at his fuedal master's bidding. Fuedalism is not a Bonus for Knights, it is a requirement.
And finally, of course, the late-game Tech Tree is an afterthought, as it was in Civ V: the technologies and capabilities of the Modern, Atomic and Information Eras are almost completely lacking.
Where are the canals? Where are the great Dams that not only provide electric power and irrigation but also Change the Landscape!? Where's the Chunnel? Where is Containerized Shipping that vastly increases Trade and Revenue late in the game (post 1950s)? Where are developments like the General Staff (Industrial Era)? Where's the 'American Method' of Production Line manufacturing (Ford's River Rouge Plant, Stalin's Kharkov Tractor Works) that hugely increased production almost regardless of the skill of the worker? For that matter, where are the late Renaissance International Banking Families (Fuggers, Rothschilds, etc) who provided governments with another source of Ready Money just when the cost of armies (with Bombards, muskets, and other expensive toys) and fortifications (the Vauban or Italian Trace geometric forts) was going through the roof?
I will stop now before I start Frothing at the Keyboard.
In respect to the Tech Tree, so far, Civ VI is no improvement at all over Civ V. The addition of a separate Civics Tree does not make up for lack of thought in implementing either Tree.
