They can't stop CSAM because of the tradeoff against privacy, not for technical reasons. AI development requires expensive, specialized hardware. Just not really comparable things.
Does it though? I can run LLaMA on my desktop. Training requires hardware which is more expensive if you want it to run quickly, but it's in the range of tens of thousands of dollars. That's not beyond the means of many individuals, much less organizations. And in a few years it will be hundreds of dollars.