Earlier quoted context omitted.
Since eCall uses 112 infrastructure, it does not need subscriber identity, as the call will be accepted by any network in range.
This is no longer reliably the case, because the carrier is legally required to provide a minimum set of information about the caller (its location) to the emergency services, which many cannot fulfill if the call was made without a SIM. In the past they handled the call without that information, but after an incident in 2013 the court ruled that the requirements also must be fulfilled without a SIM (0). So some carr…
Apparently the lack of emergency calls without SIM is due to pre-existing german practice because of some "misuse" of emergency calls.
I have no words that would not end up in things that might necessity calling 112...