It is disingenuous and/or ignorant to suggest that temporarily loading an email into memory for the purpose of displaying it on the users screen is the same as parsing and catagorising the text and storing the results of the analysis in a database for the purpose of manipulating the user.
I may be wrong, but I think they were referring to things like spam detection, malware detection, possibly search indexing, and such rather than just "temporarily loading an into memory for the purpose of displaying it."
At best, you could search headers if they aren't encrypted.
Until a viable ciphertext search scheme arrives. (there are some, but everyone I've seen has some caveat or hole)
I don't think users actually care though. Google's attempt to redefine "end-to-end encryption" to include decrypting something mid route bothered me. This... meh.
Still no comment on Turing?