You should not even respond to these. Responding gives them some valuable information about your phone number. Just junk it + report as spam.

I wonder, how this in affects modern software stack that have AI with the AI Call Screening which will ask questions, you can automatically identify certain dimensions: phone is active -- phone has a plan,-- phone is a Pixel or iPhone with a specific minimum model and OS ver ?

Then because of the leak side channel effect they can further future target calls such as coming from google about your problem with "your pixel 9 or 10?"