dji has also added not desirable stuff without telling anyone.
I'm not sure what you mean. Please do explain.
I assume you're asking for examples. I don't know how after reading the forums you don't know any. Unless you treat them as unconfirmed knowledge, and therefore non-existent. While I am not able or not willing to confirm most of these as well, I do keep them in mind.
Here are a few which I can remember right now.
1. It was suggested that in firmware C1_FW_V01.06.0000 the power output of either RC, AC or both was nerfed. One Dji technician admitted it, later all were saying it is not true. Then Dji started saying that they keep the drone parameters within original spec after update, without discussing what was changed in detail. One person was able to confirm the change with a power meter, but results were questionable, as it isn't easy to correctly measure the power, especially in the AC - RC is easier. When I reached to my sources, I only got an answer that it is possible to control power of the transmitter by software and the drone does that, and the protocol allows RC firmware to remotely change power output in the AC.
2. Unofficial batteries rejection - one of the FW updates is believed to cause the drone no longer start if a non-dji battery is inserted. I don't have such battery, so I was never interested in details, versions etc. I also don't know if it was only one version, or if this continues. My sources confirm that Flight Controller recognizes unofficial batteries, so it is very easy for it to block starting motors by software when such battery is inserted.
3. DroneID protocol. While this doesn't concern Ph3 drones, all newer are affected. This was confirmed by many sources and evidence is hard. So Dji added the functionality which makes drones broadcast their position, heading, FC serial number, registration information, flight time, battery level, work mode etc. Anyone with a proper receiver can access that information. Dji made official statement about this functionality 8 months after it was introduced. For 8 months, they played dumb. There was also no option to disable this broadcast until the official reveal happened. Some of my sources claim the reveal was earlier than planned, because hackers noticed it, decrypted the protocol and published its specification - making much easier to receive it.
That's it for now, this post is getting long.