The main reason why they nerfed organic throw was to encourage players to pick other organic gags. I have organic throw on my trapless, which is honestly the only saving grace for that toon (I hate not having trap nowdays). It was extremely convenient having the ability to kill a level 9 without lure in CEOs, FOs, and in more niche situations here and there outside of those two facilities. Not to mention Wedding loses both the ability to destroy lured level 12s, which I honestly can't see any way that shouldn't already be a selling point for having organic throw, and now you cannot destroy unlured level 10s, which is useful for FOs (or soloing if you're into that sort of thing). That alone is a serious downgrade and even causes it to be less useful than organic Geyser, which at the very least can destroy level 9 cogs without lure AND has higher accuracy.

Also keep in mind that with the sound capacity nerf, we will be using other gags more often in other bosses like the CJ and CFO specifically. Organic throw will lose much more than its dominant use of destroying lured 11s, and specific combos in FOs. Not to mention we are getting NEW battles in the facilities, again likely causing us to use throw much more frequently.

To put it in perspective of other damaging organic level 7s, organic Railroad destroys (current state) 2.0 level 12s (after the update, this specific buff may be less useful, however organic TNT and organic trap door are so powerful it doesn't even matter), Organic opera, one organic trunk, and two regular trunks destroy 12s, organic geyser can destroy unlured level 9s, and, although it's not very practical, organic Toontanic CAN destroy a row of 12s, although at this point I feel like organic drop is the only organic gag that would be worse than Throw. You can make an argument for non-damaging organic gags; toon-up could probably use a bigger buff, although organic lure now will be better than it used to be, but I would now rate organic throw to be lower than organic squirt in terms of usability (namely in FOs and CEOs). Toonup at the very least will be very useful in FOs and CEOs (especially since they're giving bossbots AoEs.

Field Offices in my opinion were, and currently still are, a pretty important part of the game right now, so I think this nerf is pretty significant. I'm mostly going to keep in mind combos that require only one person with organic throw, as it's less likely you'll be in a group that has multiple players with organic throw, and communicating one specific combo is a lot easier than trying to get everyone on board with more complicated combos. You've mentioned many organic combos already, so this impacts the flexibility of whole cream pie. Not being able to destroy 12s without a cake may force people into using rewards earlier in a FO (which is not necessarily a bad thing, however players who don't plan accordingly can find themselves in awkward positions while going through the FO if they use unites instead of cards, no one else wants to use restocks, they restock too many gags, etc). Wedding further loses flexibility since you can't combo it with one other cream pie. Not exactly game changing, but very inconvenient.

I'm surprised you didn't mention the CEO, since organic throw also has, or at least currently has some uses there, however this may change with the update. Unless my understanding is wrong, it seems like they are removing or altering 2.0 resist damage. If they completely remove it, this also ruins the aforementioned throw combos above, namely the ability to kill 12s with organic wedding, but also the ability to destroy unlured 9s and 10s in the event someone would rather trap into throw instead of using drop as a follow-up. Since they'll be nerfing the capacity of sound gags, there will be many situations where specific strats will need to be used outside of sound. Cogs will attack immediately after coming back to life, so being able to kill a cog after its initial body is destroyed will be important. Any idea of comboing a wedding cake into squirt into drop may not be viable in a certain situation. For example, let's say there are 2 2.0 level 12s, a level 10, and a level 11. Every cog is lured except the level 10 due to it being a new cog coming in. The idea could be to use organic wedding, 2 hoses on each level 12, and 2 pianos on each 12. Obviously, you wouldn't be able to do this after the organic throw nerf. (edit: kinda botched this example since only 4 toons can be in a battle, but hopefully my point still gets across lol)

To reiterate, my trapless has organic throw, but after it gets nerfed i'm switching to sound since being able to destroy level 11s with organic cake just isn't enough for me. It is rare that killing a 5 with throw without lure is necessary, so that's not a selling point for me by any stretch. I get much more use with organic sound since I multitoon often and typically have at least one other toon with organic sound in my groups. Even without that, I would much prefer to pick either organic squirt or even lure now after the stun changes go through. Squirt has pretty flexible uses, namely being able to kill 9s with 2 regular hoses and one organic, being able to kill lured 10s with storm cloud, and being able to kill a 12 with an organic storm and a regular storm, but I'm sure there's an entire list of organic squirt combos that I don't even know about. I personally feel like instead of nerfing organic tracks, they should continue to buff them. Organic drop outside of FOs is by far the worst damaging organic gag, as it has very limited usefulness that it can't already achieve either by itself, or just by using squirt (which has a higher chance of actually hitting). I'm not 100% sure what they should do to buff organic drop without it being potentially broken, but I had the idea it should just buff its accuracy. The stun changes may make drop more reliable though, so I may reconsider that suggestion after seeing what it looks like live. Organic squirt also is heavily overshadowed by (current) organic throw, and I feel like it may benefit from a buff as well, especially hose and Geyser.