Client-Side-Scanning is going to be implemented by the messaging app vendor. This means that it’s limited by OS or Browser sandboxing . Therefore it’s definitely limited to what the messaging app has access to. However, I’m not sure what the actual scope would be, meaning if all accessible images are going to be scanned or only the one being transmitted to someone.
Germany has the same problems. After the reunification they merged the east and west state railway companies into a private enterprise, the Deutsche Bahn AG. Since then, the service progressively became worse and the prices unaffordable.
They engaged in a downward spiral of cutting infrastructure investments and reducing coverage/offer and having less private travellers. Now the infrastructure is such a bad state, that the bad quality of the service is a running gag in Germany. Voyagers now expect their train being late and hope that it will not be cancelled last minute.
In the last couple of years, there has been a push to invested in the infrastructure, but it’s too little too late and it’s going to take decades to make the train an attractive option again.
One of the reason why they are still getting by financially, is because the have very good marketing.
Here’s a good video about it. It’s in German, but you can get the English auto-translation.