Ah, I think you're confused by the way the preceding paragraph ends ("Apple told WIRED that it also plans to continue working with child safety experts [...]").
The paragraph you're quoting ("'Technology that detects...scope of the problem.'") is entirely commentary from Erin Earp at RAINN, and is what was added by WIRED with the edit.
And, sorry to nitpick, but "Countering CSAM is a complicated and nuanced endeavor [...]" has always been the last paragraph (both before and after the edit).
The last paragraph of the story is a concluding statement by the author on the difficulty of countering CSAM, and it says no such thing.
The announced opt-in feature for iCloud family accounts (Communication Safety for Messages) will scan content that is sent and received by the Messages app, and alert the associated parent or caregiver directly, without informing Apple.
The paragraph you're quoting ("'Technology that detects...scope of the problem.'") is entirely commentary from Erin Earp at RAINN, and is what was added by WIRED with the edit.
And, sorry to nitpick, but "Countering CSAM is a complicated and nuanced endeavor [...]" has always been the last paragraph (both before and after the edit).