I started up a game of CIV VI for the first time in a while because of the trade hotfix yesterday. I was keeping a keen eye on trade offers and came to realize that the AI values Diplomatic Favor far too highly. The amount of gold per turn the AI is (still) willing to pay for Diplomatic Favor is so high that it's not worth it to amass Diplomatic Favor. Consider that even though you sell off all your (20) Diplomatic Favor for a ton of gold per turn, you can still vote in congress because you get free votes. What does the diplomatic favor provide? Whatever the result of the vote, it's unlikely to make any significant impact. Beneficial effects are often shared anyway like buildings in districts or purchasing units. The AI tends to never place votes on placing burdens on someone. They will always go for something that benefits themselves directly, which tends to also benefit you. In my current game I am making bank and voting for free on pointless votes. Who cares if buildings are constructed quicker in the Government Plaza? I'd rather have 200 gold per turn in the Classical era, buy anything I want, have 0 Diplomatic Favor and vote anyway. Not only is 200 gold per turn in my pocket 200 gold per turn in my pocket, it's also 200 gold per turn less in their pockets. With the massive cost of upgrading units now, it's worth it more than ever to have gold. The AI will prefer adding a second vote on increased production for buildings in government plaza (for all) than upgrading its entire army.