I didn't see anything stated in the patch notes about changes made to Client Stating Independent People (if I missed it, I'd be happy to have it pointed out), but after playing for a bit on the new DLC/Update it became clear that Client States were badly nerfed to the point that it has effectively removed all viability from Client Stating. Previously Client Stating would net ~150 Money/Influence/Science per turn (among the other bonuses), which was a substantial (and arguably too much) amount of return on investment that was not only worth it, but very powerful especially in the early game and gave flexibility to playing with Independent People. After the update, Client States generate ~15 (at most) of each of these FIMS per turn; these numbers are negligible in the mid to late game just on their own, but considering that you must continue to invest heavily into Independent People to maintain the required 60% share, ultimately this turns into a net loss on both Influence and Money in most situations, and that isn't even accounting for the heavy up front investment of signing the treaties themselves.

My question is, why? Client States were arguably too powerful before (though considering how much investment was required to keep a Client State, let alone multiple, I think that is debatable), but a nerf to this level effectively makes Client Stating not just worthless, but actually harmful overall as you wind up with a net loss almost across the board. Adding the ability to Client State Independent People was one of the best additions to the game, hands down, and made Indepenedent People actually worth investing in for more than just to Assimilate. But now, it's just back to Assimilation or Annihilation, which hardly feels like the only intended options. Perhaps increasing the FIMS for Client Stating up around 75-100 would be a more palatable nerf, but honestly I think that a scaling system would make the most sense. 50 FIMS per turn to start, increasing at a rate of +1 for every turn that they have been Client Stated. If you establish your first Client State on turn 50, by turn 150 you're looking at 150 Money/Influence/Science per turn if you maintain the Client State the entire time, which feels like a fair return on investment. It also incentivizes Client State sniping to try and mitigate that scaling factor and just adds more overall strategy to the interaction with the Independent People, beyond just deciding to invest to Assimilate or just outright exterminate them.

TLDR; Client State yields have been nerfed into the ground, and I'm curious why.

The Bonny hotfix preview notes include a line for "Fixed an issue where Independent Peoples would not build regular Districts or Infrastructures."  If IPs aren't building anything at all (or are building significantly less) in the current release, that could lower their treaty yields because I think the yields are based on how large/developed the IP's city is.  Hopefully we'll see those yields go back up if this patch lets them build again.

That said, I agree with you that the original Science treaty was probably too overpowered and could use some scaled reining in.

That makes a lot of sense! Thank you for helping to make sense of something that was genuinely super deflating. As I said, I absolutely loved the Client State mechanic (it could use some work, but overall it was a great baseline addition) as a way to make IPs more than just targets for war/Assimilation, but in their current state they simply aren't worth investing in (outside of potential Assimilation). I'd love to see even more functionality added to the Client State mechanic (perhaps unique bonuses for each IP, and/or a rebalance to holding a Client State in the late game which is quite difficult with multiple Humakind level AI in the game), but at this point just getting things back to where they were (or close to it) would be better than what it currently is.

I'm with you. Hopefully after this next patch comes out, Independent Peoples will be even more worthwhile investing in than before, because they're also supposed to build infrastructure as well as districts, which might increase their bonuses and will definitely make them pay off more if and when you Assimilate them, too.  Much less time spent playing catch-up to build all those basic infrastrutures.

I would love to see unique bonuses for each IP, and created a thread about a year ago after the new IP rules came out; I'd love to hear your input and maybe get a "bump".

https://community.amplitude-studios.com/amplitude-studios/humankind/forums/169-game-design-and-ideas/threads/50677-idea-give-independent-peoples-distinct-benefits?page=1#post-363759

Done!

I'm actually in the process of writing up my own (admittedly probably too long XD) thread with ideas, and I mention unique traits for IPs in it (though not as detailed as your thread). Thank you for pointing it out for me to bump, and I'll be sure to reference it in my own thread as well!

The cost/benefit ratio of turning an independent people into a client state isn't usually worth it. I usually just take independent peoples over by force.

Yes, the patch that fixed Independent People not building Districts/Infrastructures did fix the "nerf" (which was actually just a bug) that I originally posted about, but even after the patch it still does appear that the values gained for Client Stating are still much lower than they had been previously. Which, to your point, still makes them not worth Client Stating (unless you're going for the Singaporeans). I still think Independent Peoples need work to make Client States worth it, but at least patching that bug got it going in the right direction.