It just went totally away from prior values of historical accuracy, education, introduced some wacky gameplay mechanics, the move to 3d hugely gimped the visual beauty of earlier games and also created smaller maps with more cropped camera views.. it was just ass.
I don't feel guilty spoiling that the climax of the campaign was the ottoman empire and some ex crusader Knights fighting in the heart of the Amazon in search of the fountain of fuckin' youth laaawl
Also, there was a colossal graphical downgrade, in the days before everyone picked up on that stuff, between teaser screenshots and the game.
You gotta be kidding me.
AoE was never historically accurate, always just inspired.
AoE3 is just... even less accurate.
AoE3 meanwhile brought one of the best things to the series, a way to give players an actual agenda, a build possibility to fine-tune to their playstyle, in the form of the home cities.
Something to make the nation you play actually
yours in a very mild rpg manner and not just some choice from a list.
I loved the hell out of that when playing, no matter if offline or online.
It also brought actually different nations to play, instead of being like AoE1&2 where every nation is pretty much identical apart from maybe a special unit or two and some minor tech differences.
And the campaign was just a majestic piece of cheesy storytelling. So absurd you gotta love it.
Though I can understand how someone would be upset if you expected anything historically accurate.
Not saying it was perfect, as it sure wasn't.
For example, I just love turtling and that is straight up impossible in AoE3. Walls are even less durable than in previous installments, gunfire units shoot right through them (yes, really) making them almost entirely useless and you can't build them over railroads making it impossible to build useful walls on some maps. At least some nations can go for pretty OP towers with the right hometown abilities.
Balance was also an issue with so many so different nations - but then again, better that way around than the AoE1&2 way with all nations being mostly the same. Still, they didn't even manage to make the different choices within the nations' hometowns on par with each other.
Online play became impossible to get into with most players being veterans of 10+ years so anyone trying to even get started would just be immediately disheartened by getting their asses handed to them nonstop.