Well, the previous patch was overshadowed by making amenities almost irrelevant, this time it's spying that's been randomly selected for decimation. It suddenly seems that FXS is trying to dull their game whenever possible.
Yes, spying on allies allowed something that can be called an exploit, but, as such, the possibility of spying on allies wasn't the flaw that needed a hammer. It was this arbitrary locking into friendships and alliances for a fixed term that badly needed a revision. Axing out this unbreakable vow, which is more of the Harry Potter world than this, would have been much better.
It is this unbreakability of friendships and aliances that opens the way to all kinds of exploits and makes game more rigid, static and dull. You get a civ to be friends and allies and that's it - your diplomacy with them is ended. You can genocide the rest of the world and they will be "wow, good job, what a busy bee you are!" All those negative modifiers you accumulate with them afterwards count for nothing, they'll renew friendship on the turn of expiry. What a boring state of affairs.
And now, you can't spy on allies, so the game becomes even more rigid and dull. Rosey nosey holdy handy, bffs for life. More difficult to stop allies from victory? Yes, but achieved in an unimaginative and dull way. It is trying to rectify a situation, that was caused by one arbitrary condition, by introducing another arbitrary condition, both conditions very simplistic and greatly limiting the freedom of action for the player.
In comparison, Civ IV has a vastly superior diplomacy system. Friendlier leaders will not plot on you if they're 'pleased', with more devious ones you need to reach the status 'friendly' to be safe, but there's no fixed term locking of relations, apart from 10 turns safety net when you give into a demand or they give into your demand. Every action changes the diplo modifiers between civs and if behaving too aggressive you can drop out of the safe zone into the line of fire. The situation in the world is much more dynamic and interesting. Civ VI already suffers from too much static post mid game and they make it even more so.
The garbage bin of history if overflowing with treaties of 'eternal frienship and brotherhood' that were torn apart at the first opportunity. Who are those divine overseers who monitor the strict observation of those fixed term friendships? Please, FXS, stop drifting into this simplistic naive non-reality. Bring in carrot and stick approaches instead of these made up arbitrary conditions that everyone impeccably observes on the word of honour.
Two monthly patches, two very bad changes. Now I dread of what's still to come.