Yes, but at some point it doesn’t matter. The AI is trained to replicate human writing. There will be a point where it becomes so good that the result is a perfect replica, where it is indistinguishable from human text. I.e. even a perfect detector will not be able to confidently declare it as AI written, not ever. Because there is no difference.
You should report it to the Bundesnetzagentur, spam calls are illegal.
https://www.bundesnetzagentur.de/DE/Vportal/AnfragenBeschwerden/Beschwerde_Aerger/start.html