I believe that one important reason as to why so many people feeling/felt concerned about AoEIV is due to the bad marketing for this game. Seriously I don’t know what they thought but it failed on almost all aspects.
I can totally relate to the concerns and worries if you weren’t part of the CB at this moment.
Well, that’s just not true.
I know this is not the majority opinion, but I like it this way, with more symmetric Civs.
This game will end with a lot of Different Civs. You simple cannot make entire different unit roster for each. So having shared units across all of them is very good in my eyes.
Every civilization have Infantry, Pikemen, Cavalary, Archer… so why people want unique units for them…? The important part is that they look distinct. Yeah, it’s the same “archer” unit, but just by looking different, for me it’s enough.
I don’t see how it improves gameplay breaking the rock-paper-scissors Age mechanic just for the sake of adding ‘unique’ units that ends being a gimmick.
The truth is that it is an imbalance of unique units per civilization, that can be fixed by adding more in the future.
It’s not about breaking rock-pap-sciss systeme, it’s about hading specificity, like a spearman with 2 range ; an bowman with more less hp/more resistance etc… if i can do the same bow/pik rush with mongol and china with juste a different skin, it’s seem a little disapointing specificly when the game is suppose to be “asymetric” (and devs have insist a lot about that).
But i think i just need to wait for aom2 if i want a real asymetry ^^
Each of these civilizations will be different from each other: they will have different ways of moving and attacking, as well as managing resources, that is to say, they will not be eight cloned civilizations with mere aesthetic changes or changes in the number of units. Each of them will be handled differently and will require the player to adapt to their peculiarities. An example given by the team was that of the Mongols: being a nomadic empire, all the cities can move from one place to another. This is what the team calls “asymmetry of civilizations”, or rather “semi-asymmetry” because they will share some units.
https://www.techidence.com/age-of-empires-iv-8-questions-and-their-answers/
Enlighten me with more than 20 characters
Well just paying attention to the short clips they have shown you can already tell the civs are more asymmetrical than in aoe2.
If you haven’t already, you should try Age of Empires Online via project celeste and Age of Empires 3 to see why we want different civ design.
They will share almost every unit.
They seem to share basic unit types. Such as swordsmen, spearmen, archers, and horsemen. Unless you want to argue that only some of these medieval civs were capable of using such troops, that’s how it always was going to be.
Their proficiencies will undoubtedly differ however. These aren’t mirror matchups by any means.
Adding more units a long time after release is unlikely to happen and it will cause balance issues. It works well for single player games like Total War but quite risky for classic RTS.
Or you can expect something like Steppe Lancer for Mongol or Winged Hussar for Lithuania
This is straight up breaking NDA.
Spearman with 2 range and Bowman with more stats is Unique Unit territory, just like the Longbow is basically an improved Bowman.
And all the other units, isn’t this where the Civ bonus enter…? A Civ have Infantry move 10% faster. Another have infantry have 20% more HP. Another have Pikes with higher damage, etc…
All these different bonuses make some Civs better to do something than others without presenting an army of unique units where the player thinks “what the hell these units do and how I counter them…?”
I played Age of Empires 3 a lot. I don’t like the Civ design of it, specially how it’s difficult to know across Civs what bonuses a unit does or takes.
Giving unique things like Banks to Dutch is the cool path.
Ships: no info = we don’t know if they are shared or not
You can make :
It’s a way more diverse than just said “this civ have bow which fire 20% faster than the regular one” and me with my regular stupide bad bow i will prefere spam my knigh because my knight have 20% more HP than regular one"
I don’t know how that’s a problem. If you hover to one unit there is a short description that immediately pops out, which is almost the same for the same unit type. Then you can click on it for more description and exact bonuses. Not to mention most units of the same type typically have the same animation.
Only Africa DLC could have more unique units than all AOE-4
Sad but true 
Yes, this game had many things against it that did not strengthen its popularity enough (Because here many assume that popular is equal to “better”). Its asymmetry could almost be equated with that of starcraft in some respects.
Unfourtunately its impossible to talk about asymmetry in aoe4 due to the NDA. It’s a subject that requires a lot of information and even hands on experince to see if civs truly feel different.
A small example that’s officially revealed is the longbowman. The unit is an “unrivaled archer unit” so persumably its a renamed archer with a stat boost. Additionally the aoe4 website reveals the council hall that trains longbowmen faster than an archery range. We also know that they have an ability that helps them counter cavalry. We can see that with each new piece of information the longbowman becomes more and more unique ending up as a stronger, faster training archer that is created from a free* building and can defend vs cavalry with a special ability.
If we assume that the positive opinions of beta players are representative of what the rest of the community will think it is reasonable to assume that this compounding asymmetry is present for other civs, making their unique or even generic units play very differently from other civs with the same or similar units.
To demonstrate how a lack of information prevents complete analysis of aoe4 asymmetry let’s look at the Rus cav archer and Mongol mangudai. We don’t know what age the mangudai is available in, we don’t know how the khan signal arrow ability interacts with mangudai, we don’t know if the Mongols have landmarks that buff mangudai, nor if there are any other unique bonuses that further differentiate them from a more generic horse archer. From a rus perspective we also don’t know if their horse archers benefit from landmarks or unique techs, we don’t know if the warrior monk will be effective at balancing out the hit and run tactics of a horse archer with a more static zone of control to protect siege and hold a position, nor if warrior monks can heal and if that will make warrior monk + horse archer a uniquely difficult unit comp to beat.
As always it’s better to wait for information before making judgements.