Making a statement of fact and then say “we have covered this before” is not a valid MR argument.
I think with the links pointed out in a post after you asked, you can see that there are a TON of links and stories around this that can easily be found by either scanning through this thread or looking for yourself online...believe me, I think I've read them all.
Your issue with them is a valid one IMHO; they are nothing more than either pure false assumptions based on what COULD happen and stating it as fact that it WILL happen. Many of them from the "experts" (see most of the YouTube videos on this) are simply wrong in their analysis of what Apple is doing and revert to basic hash analysis and how THAT can be wrong or bring up errors. The fact is, they do not know what Apple's version is and why it is so secure (as well as the multiple toll gate checks)
But in the detractor's defense, they are concerned that it COULD happen (however highly unlikely that it WOULD).
Examples of governments like Russia or China abusing tech and then applying that to truly free democratic countries like the USA with fairly strict laws preventing abuse around this kind of stuff does not stop people from wondering what COULD happen.
The difference here is, no government or government agency is involved in this process in any way...Apple controls the firmware on it's phone and is HIGHLY unlikely to be hacked (and when it has been, information like that being used could not be interpreted by the hackers)....which brings me to my final point I have made over and over on here:
A) Any true hacker or government with just basic abilities could EASILY get into your phone if they wanted and download the offending material directly without having to use this firmware to help them.
B) Apple already has firmware on your phone that scans images on your phone to provide data on photos like where it might be taken or the content of photos (POI's, dogs, cats, plants, etc.)...why not hack this version which is much more open to interpret pics?? Oh right, you would still have to get the info off the phone, in which case, just use option A.
C) The issue of whether Apple even has the legal right to perform what some say is an on-device "scan" for illegal material is another thing. Apple's stance is that they are anonymously "marking" what could be illegal images and even those would only be viewed (as marked photos) once YOU upload them to iCloud. So, you have the option of never using iCloud for photos and technically, nothing could ever happen no matter what you keep on your phone (unless you believe as many on this thread seem to do which is that nefarious governments/agencies will somehow break into Apple, re-program the code, giving them access to everyone's iPhone and what is stored on them...because, it happens in the movies so it must be true and happening every day now, right?)
EDIT: Spelling errors