The part where FHE requires 42X cpu and 10-20X RAM of non-FHE operations will initially keep the use cases relatively small, and we don't have Moore's progressi

The part where FHE requires 42X cpu and 10-20X RAM of non-FHE operations will initially keep the use cases relatively small, and we don't have Moore's progression to bail them out in a few years. Neither are FHE operations in these kinds of use cases heavily parallelizable. I'm also seeing some questions over side channel attacks by throwing enough data at the polynomial transforms that make up the NAND gate you're hiding the FHE'd data in, some people are claiming there has to be a way to eventually derive the encrypted value of the data you're attacking, but I don't understand any of the maths around FHE so I can't tell how big a concern those types of attacks are. From my layman's interpretation of the comments IBM'ers are responding to, I don't think a single operation under FHE is intrinsically vulnerable to side channel attacks, but I bet how FHE is used in real-world applications with iterative back-and-forth operations does potentially open up specific poorly-designed usage patterns to the classic inferential side channel attacks. If FHE becomes practical at the scale you imagine, it would dramatically raise the bar on hacking for sure, but the implementers still only need to make one mistake to give a wedge to the hackers to work with. The tokenization market (tokenize/detokenize sensitive data) just turned up the "interesting" knob to 11, though. Would take a lot of work between vendors to make real and practical, but some real promise there.