This is stupid and downright un-elegant. Crass. Classless.
I mean, I understand that artstyles can make or break a game. I also disliked for example, when Diablo took a cartoony style, because it made it look far more generic and tonally off-putting.
But there are cartoon styles and cartoon styles. And Firaxis artists's have made an incredible job here. Civ 6 looks far less generic than 5, the leader animations are incredible and far more expressive than on any civ entry, and the map is far more readable thanks to its stylization.
People who dislikes a cartoony style due to it being cartoony per se, rather than due to any other consideration is no better than the whole "Nintendo kiddy" brigade.
“When I became a man I put away childish things, including the fear of childishness and the desire to be very grown up”- C.S Lewis