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 carriers (notably all German ones) stopped accepting Emergency calls without SIM, first to not be in violation of the law but nowadays apparently due to "misuse" (?) (1).

(0) https://eur-lex.europa.eu/legal-content/EN/TXT/HTML/?uri=CEL...

(1) https://www.heise.de/en/background/112-Emergency-Call-Day-No...

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...

Isn't the network still tracking you via the modem's IMEI in that case?

Phones can call 112 without a SIM, so it might work, though I haven't tried it.

I thought this was removed due to abuse taking place with such phones

Oh hm, I don't know, and I didn't want to try by placing spurious emergency calls.

Try next time you see an emergency that you can call in, to pop your sim first. At least if it's not one where seconds count.