I think some people get too worked up and emotional over this issue. The airline has insurance coverage, and that coverage is in part to protect the company from third party claims. If individuals or groups are going to make third party claims, they would need to initiate a suit. It really is as simple as that.
Certainly not all the individuals will necessarily have a claim. The airline may mitigate or even settle those claims as it sees fit. It may be a condition of their insurance coverage that they are restricted in the negotiation or settlement it would otherwise choose to make. Any claims that are made may be successful, partially succesful, fail, be dismissed or abandoned. There is no surity in any of this, and even those claimants that do pursue their claims might spend many years doing so before the claim is eventually decided one way or the other.
This is simply a process. You might not like it, but it is. It is probably a very long process and that is why the initiation and intention to file takes place as early as possible.
If you will excuse the pun, the "flock of birds" angle is a bit of a "red herring." It may be nobodies fault when a Deer runs out in front of a car, or a tree falls on a bus. However if those risks are covered by an insurance policy, then any damage is likely covered. You can be reasonably sure the airline will recover the value of the hull, and probably the business losses associated from the loss of the hull. Likewise third parties can exercise their claims against the policy as well, although that would normally require a claim against the carrier who pass it on to their insurer. This is rather like a passenger in your car suing you for any damage they might suffer as result of a crash. In reality it all gets passed to the insurer by you. However they cannot claim directly against your policy (unless there are special circumstances) because they have no contract with the insurance company, only you the driver has that, and hence that is the process. It doesn't sound very friendly or nice, but that is how the process has to take place.
Too many "Daily Mail" indignants getting worked up over this issue in my opinion.