Barbarians are my biggest annoyance in Civ VI, but is it possible for an annoyance to be just
so annoying that sometimes you want to throw the entire game? Or does that make it something more than just merely annoying?
The problem with barbarians, as many have said, is that they're more of a threat than the AI. I don't know how they managed to code one right and not the other, but barbarians are always incredibly strong and know exactly how to take a city. They don't fool around like the AI, and what shocks me the most is they
actually bring along the right units to siege the city. Why doesn't the AI do this? Last game, Korea surprise warred me and sent two knights right to my capital; they instantly died, and they had no backup units whatsoever. Fast forward to the late game, and here comes an onslaught of barbarians - two bombards, two field cannons, two
infantry, and one battering ram. All this for a periphery city that I didn't even realize was scouted by barbs.
While I love how barbarians are actually a challenge, their spawn rate needs to be seriously adjusted to make them manageable in the early game. It is simply not fun to deal with them on turn 15; they should be unable to scout, perhaps, for a bit longer. Another idea would be to give them a combat bonus when attacking cities, because they're rather unpredictable and can level one within two turns if you hadn't prepared for them (and why would you? who would expect 5 of the most powerful units of the era showing up out of nowhere?).
I don't think we'll ever be getting more updates/fixes for this game, but if we do, barbarians should be at the very top of the list. They just make the game super RNG, and it's really frustrating when they randomly appear with the potential to absolutely ruin everything. Without anything else to worry about (districts, for example) barbarians behave the way the AI
should with the added benefit of surprise.