No, no analogy. GMail scans every email and every attachment. Server side because - of course - it’s an online service. It’s main feature is analyzing and index

No, no analogy. GMail scans every email and every attachment. Server side because - of course - it’s an online service. It’s main feature is analyzing and indexing so it’s a direct example of a killer feature based on content analysis. Even spam filters are. The same slippery slope applies there.